International Journal of Food Science and Technology 2023 1
Review
Listeria monocytogenes at the food–human interface: A review of
risk factors influencing transmission and consumer exposure in
Africa
Thulani Sibanda,1,2 Victor Ntuli,3 Swaleha Hudaa Neetoo,4 Ihab Habib,5,6 Patrick Murigu Kamau Njage,7
Angela Parry-Hanson Kunadu,8 Anthonia Helga Andoh,8 Ranil Coorey9 & Elna M. Buys1*
1 Department of Consumer and Food Sciences, University of Pretoria, Private Bag X20, Hatfield 0028, South Africa
2 Department of Applied Biology and Biochemistry, National University of Science and Technology, P. O. Box AC939, Bulawayo, Zimbabwe
3 Department of Food Science and Technology, School of Agriculture, University of Venda, P. Bag X5050, Thohoyandou 0950, Limpopo,
South Africa
4 Department of Agriculture and Food Science, Faculty of Agriculture, University of Mauritius, R
eduit 80837, Moka, Mauritius
5 Department of Veterinary Medicine, College of Agriculture and Veterinary Medicine, United Arab Emirates University (UAEU), Al Ain
P.O. Box 1555, United Arab Emirates
6 Department of Environmental Health, Food Hygiene and Control Discipline, High Institute of Public Health, Alexandria University,
Alexandria 21526, Egypt
7 Research Group for Genomic Epidemiology, National Food Institute, Technical University of Denmark, Kemitorvet, Building 204, Kgs.
Lyngby 2800, Denmark
8 Department of Nutrition and Food Science, University of Ghana, Legon P.O. Box LG134, Ghana
9 School of Molecular and Life Sciences, Curtin University, Bentley, Perth, Western Australia, Australia
(Received 1 March 2023; Accepted in revised form 6 June 2023)
Summary In African public health systems, Listeria monocytogenes is a pathogen of relatively low priority. Yet, the
biggest listeriosis outbreak recorded to date occurred in Africa in 2018. This review highlights the factors
that potentially impact L. monocytogenes transmission risks through African food value chains (FVCs).
With the high rate of urbanisation, African FVCs have become spatially longer yet still informal. At the
same time, dietary diversifications have resulted in increased consumption of processed ready-to-eat (RTE)
meat, poultry, fishery and dairy products typically associated with a higher risk of L. monocytogenes con-
sumer exposure. With frequent cold chain challenges, the potential of L. monocytogenes growth in contami-
nated RTE foods can further amplify consumer exposure risks. Moreover, the high prevalence of untreated
HIV infections, endemic anaemia, high fertility rate and a gradually increasing proportion of elderly per-
sons expands the fraction of listeriosis-susceptible groups among African populations. With already warmer
tropical conditions, the projected climate change-induced increases in ambient temperatures are likely to
exacerbate listeriosis risks in Africa. As precautionary approaches, African countries should implement sys-
tems for the detection and reporting of listeriosis cases and food safety regulations that provide
L. monocytogenes standards and limits in high-risk RTE foods.
Keywords Food safety, food value chains (FVCs), Listeria monocytogenes, ready-to-eat (RTE) foods, risk factors.
middle-income countries (LMICs) contribute a sub-
Introduction
stantial share, accounting for 72% of global DALYs
According to estimates of the World Health (Havelaar et al., 2015; Unnevehr, 2022). The African
Organization (WHO) Foodborne Disease Burden continent contributes 43% of the global DALYs,
Epidemiology Reference Group (FERG), foodborne making it the biggest contribution by a single region
diseases are responsible for 600 million illnesses and of the WHO (Havelaar et al., 2015). Among bacte-
420 000 deaths per year resulting in 33 million rial foodborne diseases, listeriosis has a compara-
Disability Adjusted Life Years (DALYs) (Havelaar tively lower incidence, varying from 0.1 to 1.3 cases
et al., 2015). Of this global burden, low- and per 100 000 population per year around the world
(de Noordhout et al., 2014). However, despite its
*Correspondent: E-mail: elna.buys@up.ac.za low incidence, invasive listeriosis has a high fatality
doi:10.1111/ijfs.16540

 2023 The Authors. International Journal of Food Science & Technology published by John Wiley & Sons Ltd
on behalf of Institute of Food, Science and Technology (IFSTTF).
This is an open access article under the terms of the Creative Commons Attribution-NonCommercial License, which permits use,
distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes.
2 Listeria monocytogenes in Africa T. Sibanda et al.
rate (Desai et al., 2019). It results in approximately
Listeriosis incidence in Africa
10 DALYs per 100 000 population, making it the
deadliest of all bacterial foodborne infections (Have- With much of the policy attention of African countries
laar et al., 2015). focused on food security (availability and affordability)
Notwithstanding the general trend of a higher bur- and the major public health challenges like malaria,
den of foodborne diseases in Africa, the incidence of HIV/AIDS and tuberculosis, food safety-related chal-
invasive listeriosis is contrastingly lower in Africa lenges tend to get less attention (Jaffee et al., 2020).
compared to high-income regions of the world (de Compared to other foodborne illnesses like salmonel-
Noordhout et al., 2014). From a total of 23 150 ill- losis, campylobacteriosis and E. coli gastroenteritis, lis-
nesses and 5463 deaths globally attributed to invasive teriosis is generally an infrequent disease. Hence, it is
listeriosis in 2010, the contribution of the African con- not a priority disease in African public health systems
tinent was only 16% (de Noordhout et al., 2014). The and its incidence in Africa is not fully understood. In
reasons for the disparity in the incidence of listeriosis general, unless a foodborne disease causes a major
in contrast to other bacterial foodborne diseases on public health or economic impact, many small out-
the continent have not been fully explored. Against a breaks and sporadic cases often go unreported and
background of a historically ‘low’ incidence of the dis- unnoticed (Havelaar et al., 2015). Like many other
ease, the biggest outbreak so far in the world was foodborne illnesses, there is no mandatory reporting of
recorded in South Africa in 2017–2018, where a total listeriosis in African countries (Grace, 2015). So far,
of 1060 laboratory-confirmed cases, and 216 deaths only South Africa has classified listeriosis as a notifi-
were reported (Thomas et al., 2020). The mismatch able condition, a consequence of the outbreak in 2018
between the historically low incidence and the occur- (Schutte et al., 2019). Moreover, the main clinical fea-
rence of an outbreak of such magnitude in Africa is tures of invasive listeriosis, such as meningitis and
likely a reflection of deficiencies in food safety systems meningoencephalitis that result from the invasion of
and knowledge of risk factors influencing L. monocyto- the central nervous system, are also common features
genes transmission dynamics in African food value chains of other bacterial pathogens such as Haemophilus influ-
(FVCs). As countries undergo economic evolution and enzae, Streptococcus pneumoniae and Neisseria menin-
move from low- to higher-income states, their food gitidis (Peltola et al., 2021). Since L. monocytogenes is
safety systems also undergo a concomitant transforma- a less frequent cause, it is often excluded in the routine
tion accompanied by diversification in diets and con- laboratory testing of cerebrospinal fluid (CSF) samples
sumer food choices (Jaffee et al., 2020; de Bruin et al., when bacterial meningitis is suspected. In an extensive
2021). This food safety system transformation was review of the burden of meningitis in Africa, Pel-
referred to by Jaffee et al. (2020) as a food safety life tola (2001) observed that about 10% of the aetiologies
cycle in which nations move from the ‘traditional’ to the of bacterial meningitis were unconfirmed. Similarly, in
‘transitional’, ‘modernising’ and the ‘post-modern’ stages a recent study on childhood bacterial meningitis in
as they transition from the low-income to middle- and Angola, only 64% of the bacterial causes were con-
high-income stages of economic development respectively. firmed (Peltola et al., 2021). From these studies, it can
In low-income countries, the spatially shorter value be surmised that the unconfirmed causes could poten-
chains, and the predominantly traditional means of food tially be a result of the less commonly implicated path-
production such as cooking close to the point of con- ogens like L. monocytogenes.
sumption can understandably reduce L. monocytogenes So far, South Africa is the only country that has ran-
transmission risks (Barrett et al., 2020). On the other domly reported cases of listeriosis over the years.
hand, rising urbanisation in middle-income countries Through its National Institute for Communicable Dis-
results in spatially elongated value chains and dietary eases (NICD) and National Health Laboratory Services
diversifications towards the consumption of animal- (NHLS), it is probably the only country with laboratory
source foods as well as processed ready-to-eat (RTE) diagnostic and surveillance capacity for the disease.
foods (Barrett et al., 2020). Despite the nutritional bene- However, despite that, the country has not been able to
fits of animal-source foods and the convenience of RTE provide any reliable listeriosis incidence data. In the
foods, these dietary trends, unfortunately, result in a dis- absence of any reliable data, an inference of listeriosis
proportionate amplification of L. monocytogenes con- incidence can only be made from the few studies so far
sumer exposure risk (Jaffee et al., 2020; de Bruin reported in Africa. One retrospective review of neonatal
et al., 2021). Thus, this review seeks to explore the dis- and central nervous system (CNS) infection records at
tinctive characteristics of African FVCs and the poten- Tygerberg Hospital in Cape Town over the period
tially attendant risks of L. monocytogenes transmission. 2006–2016, identified 51 sporadic cases with a preva-
Furthermore, the review explores the possible risk factors lence of 0.04 cases per 1000 population (Oppel
that can exacerbate listeriosis incidence in contemporary et al., 2018). In the 2017–2018 outbreak, the estimated
African settings. prevalence was as high as 4–5 cases per 100 000
International Journal of Food Science and Technology 2023 
 2023 The Authors. International Journal of Food Science & Technology published by John Wiley & Sons Ltd
on behalf of Institute of Food, Science and Technology (IFSTTF).
Listeria monocytogenes in Africa T. Sibanda et al. 3
population in the most affected districts (Thomas Traditional FVCs are typically rural value chains of
et al., 2020). In that outbreak, 50% of the cases were low-income countries. As foods are produced and con-
pregnancy-associated, and the fatality rate was 27% sumed at home, these rural FVCs are spatially short
(Thomas et al., 2020). Besides the data from South and the diversity in foods is limited, being dominated
Africa, a meta-analysis of pregnancy-associated listerio- by staple grains and fewer processed animal products
sis by Geteneh et al. (2022), identified a few studies from (Barrett et al., 2020). While poor hygiene and sanitary
Nigeria, Senegal and Ethiopia. The pooled prevalence conditions and close interaction with farm animals in
from these studies was 5.17% (Geteneh et al., 2022). these rural agri-food systems could increase the risk of
L. monocytogenes contamination of foods and lead to
a potential direct human exposure (Rodriguez et al.,
African FVCs and L. monocytogenes food safety
2021), the homecooking of food and absence of
risks
extended refrigerated storage of food, attenuates the
L. monocytogenes risk by preventing undue multiplica-
Overview of L. monocytogenes transmission pathway
tion of the psychrotolerant organism to unsafe levels.
The main source of L. monocytogenes contamination of In middle-income countries facing rapid urbanisa-
foods is the farm environment. Its chronic colonisation tion, FVCs are in the transitional stage (Barrett
of the gastrointestinal tracts of livestock species creates et al., 2019). These are spatially long value chains link-
a reservoir for the spread of the organism into soil, ing the urban population to the rural agricultural pro-
vegetation and surfaces and materials within the farm duction areas (Barrett et al., 2020). These FVCs are
environment (Rodriguez et al., 2021). Thus, raw foods dominated by informal wet markets, street vendors
such as milk and meat can directly be contaminated and small-medium processors midstream between pro-
with the pathogen at the farm and during slaughter ducers and consumers. Midstream processing increases
(Rodriguez et al., 2021). Moreover, the use of animal the diversity of foods to include perishable fresh
manure and contaminated irrigation water is an addi- animal-derived (poultry, beef, fish and dairy) and hor-
tional route of pre-harvest contamination of field crops ticultural commodities requiring preservation and
such as fruits and vegetables (Biswas et al., 2018; Gho- refrigeration (Reardon, 2015). The concentrated pur-
lipour et al., 2020). Notwithstanding the possibility of chasing power of the urban population creates a
contamination of raw foods, many human outbreaks demand for high-value processed, ready-to-cook and
of listeriosis result from contaminated processed RTE RTE foods that save consumers food preparation time
foods (Fagerlund et al., 2021). From its primary natu- (Barrett et al., 2019). Despite the benefits associated
ral source on the farm, the pathogen is disseminated with diversified diets that bring about improved nutri-
into food-processing environments through contami- tion, these transitional FVCs are unfortunately associ-
nated raw foods. Subsequently, its ability to colonise ated with huge food safety challenges in African
and persist in processing facilities often becomes a sec- middle-income countries (Waage et al., 2022).
ondary source of post-process contamination of pro- Street-vended RTE foods are a common feature of
cessed foods (Castro et al., 2018; Sun et al., 2021). the informal food market in African cities (Abrahale
et al., 2019). In South Africa, about 30% of the urban
population depends on street foods for their daily die-
Characteristics of African FVCs and potential influence
tary needs (Steyn et al., 2011). Typically, street foods
on L. monocytogenes transmission and consumer exposure
are prepared and sold by vendors on the street sides for
immediate consumption. Their safety is compromised
As African countries develop economically, their FVCs by inadvertent cross-contamination through poor han-
also undergo transformations that have an impact on food dling practices and the unavailability of running water,
safety (Waage et al., 2022). Propelled by rapid urbanisa- washing and disinfection facilities (Kok & Balkaran,
tion and growing incomes, the value chains have changed 2014). Moreover, the extended storage of foods post-
from traditional through transitional to modernising as preparation, the elevated ambient conditions of the
African countries move from low-income to middle- and African tropical climate, and inadequate or lack of
upper middle-income levels (Barrett et al., 2019). This evo- refrigeration are all factors that collectively increase the
lution in food safety systems was referred to by Jaffee risk of bacterial growth once the food is contaminated
et al. (2020) as a food safety life cycle. Given that most (Nkosi & Tabit, 2021; Oladipo-Adekeye & Tabit, 2021).
African countries are in the LMIC (low- and middle- As economic development improves into upper
income) bracket, their FVCs are predominantly in the tra- middle-income levels, FVCs become more modernised
ditional and transitional stages. The characteristics of with formal agri-businesses and food-processing enter-
these value chains and the possible attendant risks of L. prises and a dominant formal food retail sector (Jaffee
monocytogenes transmission and consumer exposure et al., 2020). The implementation of good hygiene and
(summarised in Table 1) are discussed in this section. food safety management systems in modernised systems

 2023 The Authors. International Journal of Food Science & Technology published by John Wiley & Sons Ltd International Journal of Food Science and Technology 2023
on behalf of Institute of Food, Science and Technology (IFSTTF).
4 Listeria monocytogenes in Africa T. Sibanda et al.
Table 1 Food value chain transformation stages in Africa and their potential influence on Listeria monocytogenes transmission
and consumer exposure risk
Food value Economic Potential L. monocytogenes transmission and
chain stage development stage Characteristic consumer exposure risks
Traditional Low-income • Spatially short rural agri-food systems • Low risk due to homecooking
countries (46% of • Foods are prepared and consumed at home • Risk of direct human exposure through proximity
African countries) • No processed or value-added foods to farm animals
Transitional Lower middle- • Spatially longer urban value chains domi- • High transmission risk in informal wet markets,
income countries nated by informal wet markets, street ven- street foods and artisanal processors
(42% of African dors and artisanal processors serving • High risk of exposure through the consumption of
countries) growing urban population animal-derived RTE foods.
• Processed and value-added foods (including • High risk of exposure due to pathogen growth in
RTE foods) contaminated RTE foods and inadequate cold
• Diversity in foods includes animal and per- chains
ishable foods requiring preservation and
refrigeration)
Modernising Upper middle- • Spatially long urban value chains domi- • Reduced risk due to implementation of GAP,
income countries nated by large formal food producers, pro- GHP and HACCP in formal value chains. How-
(12% of African cessors and retailers ever, the risk remains in informal markets and
countries) • Investment in cold chains street foods
• Informal food markets and street foods are
still a significant part of the value chains
GAP, good agricultural practices; GHP, good hygiene practices; HACCP, hazard analysis critical control point. Food value chain stages and character-
istics compilation was based on the review of literature (Reardon, 2015; Barrett et al., 2020; Jaffee et al., 2020).
significantly reduces food safety hazards (Jaffee et al., urban consumers has been increasing, while the share
2020). However, even with dominant modernised sys- of staple grains has been declining (Reardon, 2015).
tems in upper middle-income countries, small shops and Processed foods include low-value foods that are
informal markets continue to be major suppliers of food ready-to-cook and high-value foods that are ready to
for a significant portion of low-income consumers (Hoff- eat (Snyder et al., 2015; de Brauw & Herskowitz, 2021).
mann et al., 2019). Thus, both formal and informal FVCs Along with an increase in the consumption of pro-
co-exist and intersect as the formal retail food sector is cessed foods, is also an increase in the consumption of
frequently a major supply source for the informal sector animal-derived foods, such as meat, fish and dairy
(Gbadegesin et al., 2020). For instance, in South Africa products among the growing urban population (Rear-
and several other southern African countries, processed don, 2015). While the consumption of animal-derived
deli-meat products sourced from formal retailers are foods may be considered beneficial for human nutri-
ingredients for preparing street-vended RTE foods tion, such foods are incidentally the most frequently
(Ryan, 2019). Furthermore, the enforcement of quality implicated in foodborne disease outbreaks (EFSA &
and safety standards in formal retailers often results in ECDC, 2017; Ricci et al., 2018). In addition to dietary
rejected foods finding their way into the informal mar- changes, urbanisation and income growth are also
kets where they are sold at discounted prices to poorer accompanied by an increased tendency of consuming
urban households (Hoffmann et al., 2019). In such situa- foods away from home. As has been observed by stud-
tions, the public health risks of L. monocytogenes trans- ies in South Africa and Nigeria, a great share of the
mission can be aggravated by potential cross- food service providers in the rapidly growing African
contamination and improper storage conditions that cities are formal restaurants, and informal street food
encourage pathogen growth. vendors that serve RTE foods (Blick et al., 2018; Hoff-
mann et al., 2019; de Brauw & Herskowitz, 2021). A
wide variety of RTE foods of animal origin is found
Risk factors exacerbating L. monocytogenes
in different regions of the continent (Adeyeye, 2017;
consumer exposure and infections in African
Nemo et al., 2017; Matle et al., 2019; Gichure et al.,
settings
2020; Makinde et al., 2020; Adeyeye & Ashaolu, 2022).
Owing to their high moisture content and neutral pH,
Consumption of high-risk RTE foods
meat, fish and dairy-based products are most at risk of
As African countries urbanise and average incomes L. monocytogenes growth during storage (G
erard
grow, the dietary share of processed foods among et al., 2018; Taylor et al., 2019). Indeed, previous risk
International Journal of Food Science and Technology 2023 
 2023 The Authors. International Journal of Food Science & Technology published by John Wiley & Sons Ltd
on behalf of Institute of Food, Science and Technology (IFSTTF).
Listeria monocytogenes in Africa T. Sibanda et al. 5
profiling has identified meat-based products as the et al., 2008; Ndahi et al., 2014; Akanbi & Usoh, 2016;
highest-risk category of RTE foods, followed by dairy, Usman et al., 2016). In South Africa, prevalence rates
fish and fruits and vegetables (FDA & FSIS, 2003; of 4.3–14% were reported in RTE meat products,
Batz et al., 2014; WHO & FAO, 2022). Many of these sandwiches and salads (Christison et al., 2008; Matle
RTE meat products, such as nyirinyiri, suya, koche, et al., 2019).
and smoked fish are traditional African products now
produced for the urban informal food market by arti-
Cold chain challenges and L. monocytogenes growth
sanal and small-scale processors (Table 2). However,
potential
others such as vienna sausages and frankfurters are
exotic cooked or smoked meat products that are pro- Inadequate cold chains are responsible for huge food
duced by large formal processors and consumed widely losses in developing countries (IIR, 2020). Inadequate
across the continent (Christison et al., 2008). refrigeration equipment and chronic electricity supply
In the last few decades, the per capita consumption challenges can make the sustenance of cold chains dif-
of such high-risk foods has dramatically increased in ficult in many African countries (IIR, 2020). Gener-
Africa. A survey of food consumption changes in ally, the most common and easily discernible effect of
South Africa between 1999 and 2012 showed that the an inadequate cold chain is the food quality deteriora-
consumption of chilled ready meals and frozen pro- tion that results from the growth of spoilage organ-
cessed foods increased by 50–100% (Ronquest-Ross isms. Normally, a high level of organisms in the range
et al., 2015). In South Africa, most of the processed of 106–108 CFU g
1 is required before sensory quality
RTE meat products emanate from formal food pro- deterioration becomes evident (Poghossian
duction systems as factory-packaged or retail-sliced et al., 2019). Yet, unlike the spoilage problem, the
and re-packaged products (Matle et al., 2019). They food safety risks arising from cold chain failures may
are also important ingredients in the preparation of not be easily detectable as the growth of pathogens
street-vended foods. For example, polony, viennas and may not produce any discernible sensory effects. More-
frankfurters are used in the production of kota, a over, foodborne infections frequently result from the
street-vended sandwich that is widely consumed by consumption of relatively lower levels of microbes
South African urban populations (Steyn et al., 2011). than are required for spoilage. In more than 90% of
Although there are no systematic surveillance studies listeriosis cases, the identified RTE foods frequently
on the occurrence and contamination levels of contain at least 2000 CFU g
1 of the pathogen (Ricci
L. monocytogenes among RTE foods sold in African et al., 2018). Worse still, the concept of food safety
cities, a few random reports have been recorded. among African consumers is often misconstrued with
Prevalence rates of 4% in processed meat products negative sensorial perceptions of foods such as smell.
(suya, balangu, kilishi, dambun nama), 14% in Thus, temperature-abused leftover RTE foods can be
street-vended soy wara (a soft cheese), and 25% in consumed if the sensorial properties are deemed
smoked fish have been reported in Nigeria (Salihu acceptable (Odeyemi et al., 2019).
Table 2 Ready-to-eat (RTE) meat, fish and dairy foods with potential for Listeria monocytogenes transmission risk as they are
produced and sold in African urban areas
RTE food
category Product examples Product Description Country References
Meat Nyirinyiri Deep-fried fresh meat Kenya Gichure et al. (2020)
Koche Deep-fried beef or camel meat Kenya Werikhe et al. (2019)
Mutura Blood sausage made from goat or cow-cleaned Kenya Karoki et al. (2018)
intestines stuffed with cooked small pieces of meat
and formed into long coils
Suya Grilled meat West Africa Adeyeye & Ashaolu (2022)
Kilishi Smoked spiced meat Nigeria Ndife et al. (2022)
Polony Comminuted and cooked meat stuffed into large South Africa Cluff et al. (2017)
tubular nylon casings
Fish Smoked fish Hot smoked fish West and East Africa Adeyeye & Oyewole (2016)
Dairy Omashikwa Buttermilk Namibia Bille et al. (2007)
Wara and Soy wara Curdled cow and soy milk products Nigeria Akanbi & Usoh (2016)
Warankasi Soft white cheese made from goat or cow milk Nigeria Adeyeye (2017)
Amasi Fermented cow milk South Africa Maleke et al. (2021)

 2023 The Authors. International Journal of Food Science & Technology published by John Wiley & Sons Ltd International Journal of Food Science and Technology 2023
on behalf of Institute of Food, Science and Technology (IFSTTF).
6 Listeria monocytogenes in Africa T. Sibanda et al.
In RTE foods (whose physicochemical properties per- practices of informal food vendors (Letuka et al.,
mit growth), the cold growth ability of L. monocyto- 2021; Nkosi & Tabit, 2021; Azanaw et al., 2022). A
genes is an important food safety and public health risk. survey of street food vendors in Johannesburg, South
As a psychrotroph, L. monocytogenes is intrinsically Africa found that at least 60% of them did not know
adapted to growth under low-temperature conditions the correct temperature for the hot and cold storage of
(Saldivar et al., 2018). Besides the inherent growth abil- RTE foods (Oladipo-Adekeye & Tabit, 2021). In
ity, any fluctuations in temperature brought about by Kenya, a similar survey found that foods requiring
cold chain breaks can accelerate the multiplication in refrigeration are frequently kept at ambient tempera-
contaminated foods. Thus, foods with initially low tures by almost 80% of street vendors (Mwove
levels of the pathogen can exceed the safety threshold in et al., 2020). Moreover, many vendors keep leftover
relatively short periods. Experimental models in RTE foods for sale on the following day, sometimes without
food matrices have shown that the growth rate of the any form of preservation (Mwove et al., 2020). With
organism doubles as temperature increases from 4°C to all these challenges, the possibility of L. monocytogenes
8°C and from 8°C to 12°C (Kataoka et al., 2017; Ziegler contamination and growth presents a palpable con-
et al., 2019). As the manufacturing processes for most sumer exposure risk.
RTE products involve some listericidal heating steps, In addition to the safety hazards emanating from
L. monocytogenes contamination levels in the products informal food vendors, the consumer stage of the FVC
at the point of release from the processor are usually presents additional challenges that could amplify
low (frequently <10 CFU g
1) (Angelidis & Koutsou- L. monocytogenes exposure risk. In Europe, quantita-
manis, 2006). Dose–response models and epidemiologi- tive modelling has shown that one-third of listeriosis
cal data have shown that such low cell numbers cases are due to pathogen growth in the consumer
(including a single cell) if ingested in food, have a low phase of the value chain (Ricci et al., 2018). A survey
probability of listeriosis (Pouillot et al., 2015; Ricci of microbial hazards awareness among consumers of
et al., 2018; Sampedro et al., 2022). However, the street-vended RTE foods in Johannesburg, South
growth ability of the pathogen in refrigerated RTE Africa showed that although the majority of con-
foods amplifies the human exposure risk (Ricci sumers were aware of foodborne diseases and some
et al., 2018). Using risk assessment models, the overall pathogens, over 70% of the consumers had never
impact of in-food growth was estimated to contribute heard about L. monocytogenes (Asiegbu et al., 2016).
up to 37% of the risk of human invasive listeriosis In addition, a survey on consumer food safety perspec-
(Ricci et al., 2018). Moreover, the handling of RTE tives in Ghana, Guinea, Kenya, Tanzania, Nigeria and
foods along the value chain (e.g. retail-level slicing and Cameroon found that 67% of the consumers rely
re-packaging), further amplifies the consumer exposure mainly on sensory properties such as smell, taste and
risk. Risk assessment models estimate that retail-level appearance as criteria for safe food consumption
contamination causes a two- to four-fold risk amplifica- (Odeyemi et al., 2019; Isanovic et al., 2023). With the
tion compared to factory-prepackaged products (Ricci habit of using sensory characteristics as indicators of
et al., 2018). In many Southern African cities, RTE pro- food safety, African consumers could unwittingly be
cessed meats and cheeses are a common part of the local exposed to an increased risk of L. monocytogenes
street food culture, especially as ingredients for street- infections given the rampant practices of storing RTE
prepared sandwiches (von Holy & Makhoane, 2006). foods under growth-permitting conditions for long
Such high-risk RTE food products are often purchased periods.
from formal retail chains each day and can be kept for
long hours unrefrigerated as the food preparation goes
Populations at risk
on during the day (von Holy & Makhoane, 2006). The
growth potential of the pathogen in such foods can Susceptibility to invasive listeriosis varies among
undoubtedly be a major public health challenge. human populations. Many people are frequently
exposed to L. monocytogenes through the ingestion of
contaminated foods without showing any symptoms of
Food safety knowledge and practices of informal vendors
invasive disease (WHO & FAO, 2022). Variability in
and consumers
susceptibility is influenced by an individual’s CD4+
It is widely acknowledged that the food safety hazard T-cell-mediated immunity (WHO & FAO, 2022). Preg-
awareness and handling practices among African nant women and their newborns (<28 days), elderly
informal food vendors are poor (Mwove et al., 2020; persons, individuals with untreated HIV infections,
Letuka et al., 2021; Oladipo-Adekeye & Tabit, 2021; cancer patients, organ transplant patients and immu-
Azanaw et al., 2022). As was observed in Kenya, Ethi- nosuppressed patients are known to be among the sus-
opia and South Africa, inadequate food safety knowl- ceptible subpopulations (WHO & FAO, 2022). Due to
edge is a determining factor in the poor handling the decreased efficacy of cell-mediated immunity, HIV
International Journal of Food Science and Technology 2023 
 2023 The Authors. International Journal of Food Science & Technology published by John Wiley & Sons Ltd
on behalf of Institute of Food, Science and Technology (IFSTTF).
Listeria monocytogenes in Africa T. Sibanda et al. 7
infection is an important risk factor for the incidence associated with a high risk of mortality in cases of
and severity of invasive listeriosis (Thomas et al., invasive listeriosis (Scobie et al., 2019).
2020). With about 25.6 million people living with HIV,
sub-Saharan Africa accounts for two-thirds of the
Regional food trade and globalisation
global burden of HIV/AIDS (UNAIDS, 2022).
Although a significant portion of this HIV-infected Global and regional trade in raw and processed food
population is on antiretroviral therapy, an estimated products is a significant part of African economies
22% are not on treatment (UNAIDS, 2022). More- (Zamani et al., 2021). Currently, most of the trade in
over, about 8% of people on antiretroviral therapy do the typical vehicle foods for L. monocytogenes trans-
not have successful viral suppression (UNAIDS, 2022). mission (meat, dairy and fishery) is in the form of
With such a disproportionately high number of indi- imports into Africa, with limited intra-Africa trade
viduals with untreated HIV infections, the risk of inva- (Zamani et al., 2021). For instance, in 2018, West Afri-
sive L. monocytogenes infections is a major concern can countries imported about 484 million tonnes of
for Africa. Using a dose–response model, Pouillot poultry meat and milk products from the EU and
et al. (2015) estimated the probability of developing North America, while South Africa imported 30% of
invasive listeriosis from ingesting a single cell of its chicken meat requirements, mostly from Brazil
L. monocytogenes to be 100-fold higher for HIV- (Makgopa, 2020; Zamani et al., 2021). Although intra-
infected individuals than the general non-susceptible Africa trade is not as prominent as food imports, the
population. Epidemiological data from the 2017–2018 more industrialised countries like South Africa export
South African listeriosis outbreak demonstrated the both raw and processed meat products to neighbour-
impact of HIV infection as a risk factor in African set- ing countries within the Southern African Develop-
tings, with a disproportionately higher number of cases ment Community (SADC) region (Makgopa, 2020).
observed among HIV-infected persons (Thomas South African companies and retail chains supply the
et al., 2020). Along with the high HIV infection rates, bulk of the processed food products sold in countries
the fertility rate is likely to be another major risk fac- such as Botswana, Namibia, Zambia and Zimbabwe
tor in pregnancy-associated listeriosis. The estimated (das Nair & Chisoro, 2016). The public health impacts
probability of developing invasive listeriosis in preg- of the regional trade were directly evident at the height
nancy is 1000-fold higher than the general non- of the listeriosis outbreak in 2018. Up to 15 countries
susceptible population (Pouillot et al., 2015). Com- (Angola, Botswana, Democratic Republic of Congo,
pared to other regions, sub-Saharan Africa has the Ghana, Lesotho, Madagascar, Malawi, Mauritius,
highest female fertility rates in the world (Atake & Mozambique, Namibia, Nigeria, eSwatini, Uganda,
Ali, 2019). In the 2017–2018 South African outbreak, Zambia and Zimbabwe) were affected by recalls of the
50% of the total cases were pregnancy-related, the contaminated polony (Olanya et al., 2019). With such
majority (87%) of which occurred in neonates wide distribution networks of processed RTE foods,
(Thomas et al., 2020). Moreover, a retrospective study the African urban food systems pose a potential risk
of pregnancy-associated listeriosis cases in South to epidemic listeriosis outbreaks.
Africa found that HIV seropositivity and anaemia
were additional risk factors (Iiyambo et al., 2022). Iron
Climate change effects
deficiency anaemia is an endemic problem in sub-
Saharan Africa with prevalence rates of up to 60% in At the current rate of global warming, annual average
some worst affected countries (Kassebaum and GBD surface temperatures are predicted to increase by up to
2013 Anemia Collaborators, 2016). It is a known risk 5°C by the end of the century (IPCC, 2021). The envi-
factor in human susceptibility to invasive bacterial ronmental effects of climate change have significant
infections (Abuga et al., 2023). impacts on the epidemiology of foodborne diseases
Another major listeriosis risk factor that is likely to (Anas et al., 2021). Several studies have provided evi-
have a big influence on Africa is population ageing. In dence for a strong correlation between ambient tem-
general, old age (>65 years) has been known to be perature conditions and the incidence of infection by
associated with a high risk of mortality in cases of foodborne pathogens such as Salmonella, Vibrio cho-
invasive listeriosis (Scobie et al., 2019). At the current lerae and Campylobacter (Reyburn et al., 2011; Jiang
rate, the global proportion of older people is projected et al., 2015; Kuhn et al., 2020; Morgado et al., 2021).
to increase (Rudnicka et al., 2020). With the rise in As for L. monocytogenes, evidence from the listeriosis
ageing, a concomitant increase in the incidence of surveillance in the EU from 2008 to 2016 showed a
multi-morbidities has also been observed (Chang seasonal pattern of cases with higher peaks during the
et al., 2019). Many of these conditions such as cardio- warmer summer months (EFSA & ECDC, 2017). At
vascular disease, liver disease and haematological the current rate, the African continent is predicted to
malignancy have been known to be co-morbidities record average temperature increases of 3.5–5.6°C by

 2023 The Authors. International Journal of Food Science & Technology published by John Wiley & Sons Ltd International Journal of Food Science and Technology 2023
on behalf of Institute of Food, Science and Technology (IFSTTF).
8 Listeria monocytogenes in Africa T. Sibanda et al.
the end of the century (Almazroui et al., 2020). On the areas can lead to an increased risk of foodborne dis-
other hand, precipitation predictions indicate spatial ease outbreaks. Burr et al. (1978) observed a strong
variations across the continent where the Northern association between water restriction times and rates
and Southern regions are projected to get drier while of childhood diarrhoea. Similarly, evidence from
the Central, East and West African regions are pro- around Africa has shown that higher precipitation and
jected to have an increasing precipitation trend flooding events are associated with a high risk of food-
(Almazroui et al., 2020). borne diseases (Horn et al., 2018; Ciss
e, 2019).
An increasing trend in ambient temperatures will
likely put a strain on cooling systems that could cause
Listeria monocytogenes food safety standards in
temperature fluctuations and enhance L. monocyto-
Africa
genes multiplication risks in contaminated foods (Hell-
berg & Chu, 2016). For instance, Christison et al. Microbiological safety standards can provide a regula-
(2008) found that core temperatures of RTE foods in tory guide that assures consumer protection against
retail delicatessens in South Africa were ranging from food safety hazards. A survey on microbiological stan-
10 to 16°C instead of the recommended range of 4– dards conducted as part of this review showed that
8°C due to warm ambient conditions. Additionally, only a few African countries have any form of stan-
elevated ambient temperatures could affect the expres- dards on L. monocytogenes in their food safety legisla-
sion of virulence genes in the pathogen within the tion (Table 3). Among these countries, the specified
environment and the potential spread of hyper-virulent standards vary in terms of the allowable limits and the
strains (Bruno Jr & Freitag, 2010; Levy et al., 2016). type of foods covered by the respective regulations
As an environmental saprophyte, L. monocytogenes (Table 3). Whereas some countries have requirements
normally exists in an avirulent state in which virulence for the absence of L. monocytogenes in one or five
genes are repressed at temperatures of 30°C and below samples of 25 g of raw and RTE products, others have
(Sibanda & Buys, 2022). Elevated temperatures at limits of 100–1000 CFU g
1 (Table 3). Moreover, the
37°C serve as a stimulus for the activation of virulence food products listed in the respective regulations also
gene expression (Sibanda & Buys, 2022). In the nor- vary with the focus seemingly on raw fishery, beef and
mal infection cycle of L. monocytogenes, the activation poultry products. The focus on raw animal and fishery
of virulence gene expression occurs inside the host as products is probably a reflection of efforts by African
the organism switches from the avirulent to the viru- countries to meet the export safety requirements to
lent state. Constitutive expression of virulence genes overseas markets (World Bank, 2022). Indeed, many
within the environment observed in some mutants LMICs successfully export safe food but are unable to
has been associated with hyper-virulence (Bruno Jr & implement sustainable food safety systems that work
Freitag, 2010). for domestic settings dominated by informal markets
Based on overall predictions of precipitation trends and food vendors (Waage et al., 2022). In view of the
for the African continent, the frequency and intensity projected rise in the proportion of susceptible popula-
of extreme weather (drought and floods) are likely to tion groups and consumption of high-risk RTE foods,
worsen (Almazroui et al., 2020). Although there is cur- it will be prudent for African countries to develop
rently limited data showing a correlation between domestic standards and regulations for the protection
drought and foodborne diseases, several factors sug- of consumers.
gest a possible increase in the risk of human exposure In countries with a higher level of formal food pro-
to foodborne pathogens (Levy et al., 2016). These duction like South Africa, the implementation of regu-
include the concentration of faecal contamination in lated standards would provide a significant level of
water sources and greater dependence on non-potable consumer protection against potential outbreaks as the
sources of water for cleaning food-processing equip- food business operator is an essential stage of ensuring
ment and domestic use in times of drought (Levy the safety of RTE products before release to the mar-
et al., 2016; Chersich et al., 2018). A study by Wang ket. Already, global guidelines for risk-based regula-
et al. (2022) in African LMICs observed that mild and tions for L. monocytogenes in RTE foods are available
severe drought was associated with a 5% increase in (CAC, 2009). However, data on the physicochemical
the risk of diarrhoea. Likewise, Iwu et al. (2022) profiles of African RTE foods, the growth potential of
observed high levels of L. monocytogenes contamina- the pathogen in the respective foods, the amount and
tion in irrigation water from semi-arid regions of frequency of consumption of the foods, the virulence
South Africa and an increased risk of human exposure potential of strains found in the African food environ-
through unintentional and intentional ingestion of ment and susceptibility profiles of African populations
such water. are necessary to understand the relative risks to Afri-
In addition, drought-induced restrictions in potable can consumers. In the aftermath of the 2017–2018 out-
water supplies, particularly in densely populated urban break, the subject of mandatory L. monocytogenes
International Journal of Food Science and Technology 2023 
 2023 The Authors. International Journal of Food Science & Technology published by John Wiley & Sons Ltd
on behalf of Institute of Food, Science and Technology (IFSTTF).
Listeria monocytogenes in Africa T. Sibanda et al. 9
Table 3 Standards and limits for Listeria monocytogenes in foods as specified in the regulations of some African countries
Countries with
standards for L.
monocytogenes Listed Foods Limits Regulation†
Djibouti Meat and fishery products <100 CFU g
1 Official Journal of the Republic of
Djibouti (Arrête
 n°2000-0728/PR/
MAEM)
Egypt Pasteurised cream, whipped cream, Absent in five samples of 1 g of Food and Agricultural Import
fermented cream, butter, cheese, product Regulations and Standards of Egypt
powdered milk, dietetic food intended for
high-risk groups, frozen raw crustaceans
and coleslaw
Kenya Meat products Absent in a 25 g sample Kenya Standard (DKS 2830: 2018)
Madagascar Seafood and aquaculture products Absent in five 25 g samples Ministry of Agriculture and Fisheries of
<100 CFU g
1 before the end of the Madagascar (ARRETE No 6235/2009)
product shelf-life
Mauritania RTE aquatic food products Absent in five 25 g samples Arrête conjoint no. 2905
<100 CFU g
1 before the end of the
product shelf-life
Mauritius Infant formula, dairy products, cheese and Absent in 1 g samples of infant Mauritius Food Regulations (GN 173 of
other RTE food products formula and dairy products 1999)
Absent in 25 g samples of cheese
<1000 CFU g
1 in other RTE products
Morocco Meat, poultry and fishery products Absent in five 25 g samples Microbiological Standards for Food of
Animal Origin, Morocco (MO1814)
Seychelles Fishery products Absent in five 25 g samples taken Export of Fishery Products (Sanitary)
before the product left the Regulations (2010) of Seychelles
establishment
Saint Helena RTE fishery products Absent from five 25 g samples taken Fish and Fish Products Regulations
before the product left the (2011) of St Helena
establishment
Tunisia RTE processed bovine, poultry and Absent in five 25 g samples before the Journal Officiel de la Re
publique
lagomorph meat products products have left the establishment Tunisienne (2013)
<100 CFU g
1 in products before the
end of shelf-life
Uganda Fishery products <1000 CFU g
1 The Uganda Gazette, The Fish (Quality
Assurance) Rules, 2008
United Republic Raw or cooked red meat sausages Absent from 25 g samples of the Tanzania Bureau of Standards (AFDC
of Tanzania product 22 (5279) P3)
†Regulations are available from the FAOLEX database (http://www.fao.org/faolex/en/).
standards for processed RTE meat products was diseases, yet it has the highest fatality rate. In Africa,
debated among authorities and industry stakeholders. listeriosis is not given much attention in public health
Based on submissions from representatives of food systems. In the absence of systems for identifying and
manufacturers and the food retail sector, the adoption reporting cases, the incidence of the disease is hard to
of the Codex 100 CFU g
1 L. monocytogenes limit for establish. However, the occurrence of the greatest out-
RTE meat products appeared to be a common agree- break in history in South Africa in 2018 is an indica-
ment (CGCSA, 2018). Ultimately, the role of govern- tion of the potential public health dangers of ignoring
ments and public health institutions in controlling and the disease in Africa. With the transformation of value
regulating the informal food sector and effective con- chains and diet diversification brought about by the
sumer risk education will be crucial in preventing big rapid urbanisation of many African countries, several
outbreaks in future. risk factors create opportunities for L. monocytogenes
transmission and consumer exposure. The increased
consumption of high-risk RTE meat, fishery and dairy
Conclusions and future directions
foods, cold chain challenges that increase the potential
On a global level, the incidence of invasive listeriosis is for pathogen multiplication, a high proportion of
comparatively lower than other bacterial foodborne listeriosis-susceptible subpopulations, inadequate consumer

 2023 The Authors. International Journal of Food Science & Technology published by John Wiley & Sons Ltd International Journal of Food Science and Technology 2023
on behalf of Institute of Food, Science and Technology (IFSTTF).
10 Listeria monocytogenes in Africa T. Sibanda et al.
food safety knowledge and climate change effects are
Ethical approval
all risk factors that could potentially exacerbate con-
sumer exposure and listeriosis outbreaks in African Ethics approval was not required for this research.
settings. As a precautionary approach, it will be neces-
sary for African countries to implement systems for
the detection and reporting of listeriosis cases. This Peer review
could be done systematically through the laboratory The peer review history for this article is available
diagnosis of meningitis and maternal infections, espe- at https://www.webofscience.com/api/gateway/wos/peer-
cially where the common bacterial causes are excluded. review/10.1111/ijfs.16540.
Furthermore, such laboratory-based surveillance
should be enhanced by genomic surveillance tech-
niques like whole-genome sequencing that improve the Data availability statement
efficiency of outbreak detection and epidemiological Data sharing not applicable - no new data generated
identification of implicated RTE foods. In addition,
food safety regulations that include L. monocytogenes
standards and limits in high-risk RTE foods will be References
necessary to provide a layer of consumer protection.
Abrahale, K., Sousa, S., Albuquerque, G., Padra~o, P. & Lunet, N.
In light of the wide diversity of potentially high-risk (2019). Street food research worldwide: a scoping review. Journal
African RTE products, a risk profiling of these foods of Human Nutrition and Dietetics, 32, 152–174.
with regards to the ability to support L. monocyto- Abuga, K.M., Nairz, M., MacLennan, C.A. & Atkinson, S.H.
genes growth under the commonly used temperature– (2023). Severe anaemia, iron deficiency, and susceptibility to inva-
sive bacterial infections. Wellcome Open Research, 8, 48.
time conditions of storage is necessary as a basis for Adeyeye, S.A.O. (2017). A preliminary study on the quality and
customised food safety standards for African settings. safety of street-vended warankasi (a Nigerian soft white cheese)
Other mitigatory measures should include consumer from Ibadan, Oyo state, Nigeria. British Food Journal, 119, 322–
risk education and dietary guidelines for listeriosis- 330.
susceptible subpopulations. Adeyeye, S.A.O. & Ashaolu, T.J. (2022). A study on polycyclic aro-
matic hydrocarbon and heavy metal concentrations of commercial
grilled meat (suya) and smoked catfish (Clarias gariepinus Burchell,
1822) fish from south-west, Nigeria. Polycyclic Aromatic Com-
Acknowledgments
pounds, 42, 3281–3290.
The authors acknowledge financial support from The Adeyeye, S.A.O. & Oyewole, O.B. (2016). An overview of traditional
– fish smoking in Africa. Journal of Culinary Science and Technology,Australia-Africa Universities Network (AAUN) Part- 14, 198–215.
nership Research and Development Fund 2018. Akanbi, B.O. & Usoh, E.A. (2016). Safety of street-vended soy wara
in Nigeria. Journal of Food Protection, 79, 169–173.
Almazroui, M., Saeed, F., Saeed, S. et al. (2020). Projected change
Author contributions in temperature and precipitation over Africa from CMIP6. Earth
Systems and Environment, 4, 455–475.
Thulani Sibanda: Conceptualization (lead); formal anal- Anas, M., Sami, M.A., Siddiqui, Z., Khatoon, K., Zeyad, M.T. &
ysis (lead); visualization (equal); writing – original draft Malik, A. (2021). Impact of climate change on the incidence and
(lead). Victor Ntuli: Conceptualization (equal); writing – transfer of food- and water-borne diseases. In: Microbiomes and
original draft (equal). Swaleha Hudaa Neetoo: Concep- the Global Climate Change (edited by S.A. Lone & A. Malik). Sin-
– gapore: Springer.tualization (equal); visualization (equal); writing Angelidis, A.S. & Koutsoumanis, K. (2006). Prevalence and concen-
original draft (equal); writing – review and editing tration of Listeria monocytogenes in sliced ready-to-eat meat prod-
(equal). Ihab Habib: Conceptualization (equal); writing ucts in the Hellenic retail market. Journal of Food Protection, 69,
– original draft (equal). Patrick Murigu Kamau Njage: 938–942.
Conceptualization (equal); writing – original draft Asiegbu, C.V., Lebelo, S.L. & Tabit, F.T. (2016). The food safety
knowledge and microbial hazards awareness of consumers of
(equal). Angela Parry-Hanson Kunadu: Conceptualiza- ready-to-eat street-vended food. Food Control, 60, 422–429.
tion (equal); writing – original draft (equal). Anthonia Atake, E.-H. & Ali, P.G. (2019). Women’s empowerment and fertil-
Helga Andoh: Writing – original draft (equal). Ranil ity preferences in high fertility countries in sub-Saharan Africa.
Coorey: Funding acquisition (equal); writing – original BMC Women’s Health, 19, 1–14.
Azanaw, J., Engdaw, G.T., Dejene, H., Bogale, S. & Degu, S.
draft (equal). Elna M. Buys: Conceptualization (lead); (2022). Food hygiene knowledge, and practices and their associated
funding acquisition (lead); project administration (lead); factors of street food vendors in Gondar city, Northwest Ethiopia,
resources (lead); supervision (lead); visualization 2021: a cross-sectional study. Heliyon, 8, e11707.
(equal); writing – review and editing (equal). Barrett, C.B., Reardon, T., Swinnen, J. & Zilberman, D. (2019).
Structural transformation and economic development: insights
from the Agri-food value chain revolution. Pp. 1–56. Ithaca, New
Conflict of interest York: Dyson School of Applied Economics and Management,
Cornell University. http://barrett.dyson.cornell.edu/files/papers/
The authors declare no conflict of interest. BRSZ
International Journal of Food Science and Technology 2023 
 2023 The Authors. International Journal of Food Science & Technology published by John Wiley & Sons Ltd
on behalf of Institute of Food, Science and Technology (IFSTTF).
Listeria monocytogenes in Africa T. Sibanda et al. 11
Barrett, C.B., Reardon, T., Swinnen, J. & Zilberman, D. (2020). de Bruin, S., Dengerink, J. & van Vliet, J. (2021). Urbanisation as
Agri-food value chain revolutions in low-and middle-income coun- driver of food system transformation and opportunities for rural
tries. Journal of Economic Literature, 60, 1316–1377. livelihoods. Food Security, 13, 781–798.
The article describes the transformations in agri-food value chains in de Noordhout, C.M., Devleesschauwer, B., Angulo, F.J. et al.
low- and middle income countries. The artilce was relevant in our (2014). The global burden of listeriosis: a systematic review and
characterisation of African food value chains and the connection we meta-analysis. The Lancet Infectious Diseases, 14, 1073–1082.
sought to explore in the transmission risks of L. monocytogenes. Desai, A.N., Anyoha, A., Madoff, L.C. & Lassmann, B. (2019).
Batz, M., Hoffmann, S. & Morris, J.G.J. (2014). Disease-outcome Changing epidemiology of Listeria monocytogenes outbreaks, spo-
trees, EQ-5D scores, and estimated annual losses of quality- radic cases, and recalls globally: a review of ProMED reports from
adjusted life years (QALYs) for 14 foodborne pathogens in the 1996 to 2018. International Journal of Infectious Diseases, 84, 48–
United States. Foodborne Pathogens and Disease, 11, 395–402. 53.
Bille, P.G., Buys, E. & Taylor, J.R.N. (2007). The technology and European Food Safety Authority (EFSA) & European Centre for
properties of Omashikwa, a traditional fermented buttermilk pro- Disease Prevention and Control (ECDC) (2017). The European
duced by small-holder milk producers in Namibia. International Union summary report on trends and sources of zoonoses, zoo-
Journal of Food Science and Technology, 42, 620–624. notic agents and food-borne outbreaks in 2016. EFSA Journal, 15,
Biswas, S., Niu, M., Pandey, P. et al. (2018). Effect of dairy manure e05077.
storage conditions on the survival of E. coli O157:H7 and Listeria. Fagerlund, A., Langsrud, S. & Møretrø, T. (2021). Microbial diver-
Journal of Environmental Quality, 47, 185–189. sity and ecology of biofilms in food industry environments associ-
Blick, M., Abidoye, B.O. & Kirsten, J.F. (2018). An investigation ated with Listeria monocytogenes persistence. Current Opinion in
into food-away-from-home consumption in South Africa. Develop- Food Science, 37, 171–178.
ment Southern Africa, 35, 39–52. Gbadegesin, J., Pienaar, M. & Marais, L. (2020). Housing, planning
Bruno, J.C., Jr. & Freitag, N.E. (2010). Constitutive activation of and urban health: historical and current perspectives from South
PrfA tilts the balance of Listeria monocytogenes fitness towards life Africa. Bulletin of Geography, Socio-Economic Series, 48, 23–34.
within the host versus environmental survival. PLoS One, 5, G
erard, A., El-Hajjaji, S., Niyonzima, E., Daube, G. & Sindic, M.
e15138. (2018). Prevalence and survival of Listeria monocytogenes in vari-
Burr, M.L., Davis, A.R. & Zbijowski, A.G. (1978). Diarrhoea and ous types of cheese — a review. International Journal of Dairy
the drought. Public Health, 92, 86–87. Technology, 71, 825–843.
Castro, H., Jaakkonen, A., Hakkinen, M., Korkeala, H. & Geteneh, A., Biset, S., Tadesse, S., Admas, A., Seid, A. & Belay,
Lindstro€m, M. (2018). Occurrence, persistence, and contamination D.M. (2022). A vigilant observation to pregnancy associated listeri-
routes of Listeria monocytogenes genotypes on three Finnish dairy osis in Africa: systematic review and meta-analysis. PLOS Global
cattle farms: a longitudinal study. Applied and Environmental Public Health, 2, e0001023.
Microbiology, 84, e02000-17. Gholipour, S., Nikaeen, M., Farhadkhani, M. & Nikmanesh, B.
Chang, A.Y., Go
mez-Oliv
e, F.X., Manne-Goehler, J. et al. (2019). (2020). Survey of Listeria monocytogenes contamination of various
Chronic multimorbidity among older adults in rural South Africa. environmental samples and associated health risks. Food Control,
Bulletin of the World Health Organization, 97, 10–23. 108, 106843.
Chersich, M.F., Wright, C.Y., Venter, F., Rees, H., Scorgie, F. & Gichure, J.N., Kunyanga, C.N. & Imungi, J.K. (2020). Processing
Erasmus, B. (2018). Impacts of climate change on health and well- variations, nutritional and sensory quality of ethnic deep-fried
being in South Africa. International Journal of Environmental meats from Kenyan pastoral communities. African Journal of Food,
Research and Public Health, 15, 1884. Agriculture, Nutrition and Development, 20, 16046–16062.
Christison, C.A., Lindsay, D. & von Holy, A. (2008). Microbiologi- Grace, D. (2015). Food safety in low and middle income countries.
cal survey of ready-to-eat foods and associated preparation sur- International Journal of Environmental Research and Public Health,
faces in retail delicatessens, Johannesburg, South Africa. Food 12, 10490–10507.
Control, 19, 727–733. Havelaar, A.H., Kirk, M.D., Torgerson, P.R. et al. (2015). World
Ciss
e, G. (2019). Food-borne and water-borne diseases under climate Health Organization global estimates and regional comparisons of
change in low- and middle-income countries: further efforts needed the burden of foodborne disease in 2010. PLoS Medicine, 12,
for reducing environmental health exposure risks. Acta Tropica, e1001923.
194, 181–188. This article provides a global outlook of the burden of foodborne
Cluff, M., Kobane, I.A., Bothma, C., Hugo, C.J. & Hugo, A. diseases and the disparities between developed and developing
(2017). Intermediate added salt levels as sodium reduction strategy: regions of the world. This was important in our articulation of the
effects on chemical, microbial, textural and sensory quality of pol- listeriosis risk profile of the African continent.
ony. Meat Science, 133, 143–150. Hellberg, R.S. & Chu, E. (2016). Effects of climate change on the
Codex Alimentarius Commission (CAC) (2009). Guidelines on the persistence and dispersal of foodborne bacterial pathogens in the
application of general principles of food hygiene to the control of outdoor environment: a review. Critical Reviews in Microbiology,
Listeria monocytogenes in foods. Codex Alimentarius Commission, 42, 548–572.
CAC/GL, 61, 1–28. Hoffmann, V., Moser, C. & Saak, A. (2019). Food safety in low and
Consumer Goods Council of South Africa (CGCSA). (2018). Listeri- middle-income countries: the evidence through an economic lens.
osis outbreak status report. Food Safety Initiative (Issue 08 World Development, 123, 104611.
May 2018) https://www.cgcsa.co.za/wp-content/uploads/2018/05/ Horn, L.M., Hajat, A., Sheppard, L. et al. (2018). Association between
CGCSA-FSI-Listeria-Status-Report-8-May-2018.pdf precipitation and diarrheal disease in Mozambique. International
das Nair, R. & Chisoro, S. (2016). The Expansion of Regional Journal of Environmental Research and Public Health, 15, 709.
Supermarket Chains and Implications for Local Suppliers. A Com- Iiyambo, O.J., Baba, V., Thomas, J., Sekwadi, P. & Naidoo, P.
parison of Findings from South Africa, Botswana, Zambia, and (2023). Presentation and outcomes of Listeria-affected pregnancies
Zimbabwe (Issue CCRED Working Paper No. 7/2016, WIDER in Johannesburg tertiary hospitals: a 2-year review. International
Working Paper 2016/169). https://ssrn.com/abstract=2923062 Journal of Gynecology & Obstetrics, 161, 989–996.
de Brauw, A. & Herskowitz, S. (2021). Income variability, evolving Intergovernmental Panel on Climate Change (IPCC) (2021). Climate
diets, and elasticity estimation of demand for processed foods in change 2021: the physical science basis. In: Contribution of working
Nigeria. American Journal of Agricultural Economics, 103, 1294– group I to the sixth assessment report of the intergovernmental panel
1313. on climate change (edited by V. Masson-Delmotte, P. Zhai, A.

 2023 The Authors. International Journal of Food Science & Technology published by John Wiley & Sons Ltd International Journal of Food Science and Technology 2023
on behalf of Institute of Food, Science and Technology (IFSTTF).
12 Listeria monocytogenes in Africa T. Sibanda et al.
Pirani, S.L. Connors, C. P
ean, S. Berger, N. Caud, Y. Chen, L. year (2009 to 2018) review. Comprehensive Reviews in Food Science
Goldfarb, M.I. Gomis, M. Huang, K. Leitzell, E. Lonnoy, J.B.R. and Food Safety, 19, 703–732.
Matthews, T.K. Maycock, T. Waterfield, O. Yelekc
i, R. Yu & B. Maleke, M.S., Adefisoye, M.A., Doorsamy, W. & Adebo, O.A.
Zhou). Cambridge, United Kingdom and New York, NY, USA: (2021). Processing, nutritional composition and microbiology of
Cambridge University Press. amasi: a southern African fermented milk product. Scientific Afri-
International Institute of Refrigeration (IIR) (2020). The Role of can, 12, e00795.
Refrigeration in Worldwide Nutrition. Paris: International Institute Matle, I., Mbatha, K.R., Lentsoane, O., Magwedere, K., Morey, L.
of Refrigeration (IIR). https://iifiir.org/en/fridoc/the-role-of- & Madoroba, E. (2019). Occurrence, serotypes, and characteristics
refrigeration-in-worldwide-nutrition-2020-142029 of Listeria monocytogenes in meat and meat products in
Isanovic, S., Constantinides, S.V., Frongillo, E.A. et al. (2023). How South Africa between 2014 and 2016. Journal of Food Safety, 39,
perspectives on food safety of vendors and consumers translate e12629.
into food-choice behaviors in 6 African and Asian countries. Cur- Morgado, M.E., Jiang, C., Zambrana, J. et al. (2021). Climate
rent Developments in Nutrition, 7, 100015. change, extreme events, and increased risk of salmonellosis: food-
Iwu, C.D., Iwu-Jaja, C.J., Elhadi, R., Semerjian, L. & Okoh, A.I. borne diseases active surveillance network (FoodNet), 2004-2014.
(2022). Modelling the potential risk of infection associated with Environmental Health, 20, 105.
Listeria monocytogenes in irrigation water and agricultural soil in Mwove, J., Imathiu, S., Orina, I. & Karanja, P. (2020). Food safety
two district municipalities in South Africa. Microorganisms, 10, knowledge and practices of street food vendors in selected loca-
181. tions within Kiambu County, Kenya. African Journal of Food Sci-
Jaffee, S., Henson, S., Grace, D., Ambrosio, M. & Berthe, F. (2020). ence, 14, 174–185.
Why food safety to Africa: making the case for policy action. In: Ndahi, M.D., Kwaga, J.K.P., Bello, M. et al. (2014). Prevalence and
2020 Annual Trends and Outlook Report: Sustaining Africa’s Agri- antimicrobial susceptibility of Listeria monocytogenes and
food System Transformation: The Role of Public Policies (edited by methicillin-resistant Staphylococcus aureus strains from raw meat
D. Resnick, X. Diao & G. Tadesse). Pp. 112–129. Washington, and meat products in Zaria, Nigeria. Letters in Applied Microbiol-
DC, and Kigali: International Food Policy Research Institute ogy, 58, 262–269.
(IFPRI) and AKADEMIYA2063. Ndife, J., Onwuzuruike, U.A., Ebeleagu, S.B. & Okwunodulu, N.I.
This article discusses food safety as a public health imperative in (2022). Influence of meat type on processed meat (kilishi) quality.
Africa and its relationship to economic development and public pol- FUDMA Journal of Sciences, 6, 160–168.
icy. The article was relevant in our conceptualization of the food Nemo, R., Bacha, K. & Ketema, T. (2017). Microbiological quality
safety risks associated with L. monocytogenes as a specific challenge and safety of some-street-vended foods in Jimma town, southwest-
for the African continent. ern Ethiopia. African Journal of Microbiology Research, 11, 574–
Jiang, C., Shaw, K.S., Upperman, C.R. et al. (2015). Climate 585.
change, extreme events and increased risk of salmonellosis in Nkosi, N.V. & Tabit, F.T. (2021). The food safety knowledge of
Maryland, USA: evidence for coastal vulnerability. Environment street food vendors and the sanitary conditions of their street food
International, 83, 58–62. vending environment in the Zululand District, South Africa. Heli-
Karoki, W.H., Karanja, D.N., Bebora, L.C. & Njagi, L.W. (2018). yon, 7, e07640.
Isolation, characterization, and quantification of bacteria from Odeyemi, O.A., Sani, N.A., Obadina, A.O. et al. (2019). Food safety
African sausages sold in Nairobi county, Kenya. International knowledge, attitudes and practices among consumers in developing
Journal of Food Science, 2018, 3861265. countries: an international survey. Food Research International,
Kassebaum, N.J. & GBD 2013 Anemia Collaborators (2016). The 116, 1386–1390.
global burden of anemia. Hematology/Oncology Clinics of North Oladipo-Adekeye, O.T. & Tabit, F.T. (2021). The food safety knowl-
America, 30, 247–308. edge of street food vendors and the sanitary compliance of their
Kataoka, A., Wang, H., Elliott, P.H., Whiting, R.C. & Hayman, vending facilities, Johannesburg, South Africa. Journal of Food
M.M. (2017). Growth of Listeria monocytogenes in thawed frozen Safety, 41, e12908.
foods. Journal of Food Protection, 80, 447–453. Olanya, O.M., Hoshide, A.K., Ijabadeniyi, O.A. et al. (2019). Cost
Kok, R. & Balkaran, R. (2014). Street food vending and hygiene estimation of listeriosis (Listeria monocytogenes) occurrence in
practices and implications for consumers. Journal of Economics and South Africa in 2017 and its food safety implications. Food Con-
Behavioral Studies, 6, 188–193. trol, 102, 231–239.
Kuhn, K.G., Nygard, K.M., Guzman-Herrador, B. et al. (2020). Oppel, K.B., Holgate, S.L. & Finlayson, H. (2018). A retrospective
Campylobacter infections expected to increase due to climate review of Listeria monocytogenes infection at Tygerberg Children’s
change in northern Europe. Scientific Reports, 10, 13874. hospital, Cape Town, South Africa, from 2006 to 2016: is empirical
Letuka, P., Nkhebenyane, J. & Thekisoe, O. (2021). Street food han- ampicillin still indicated after the first month of life ? South African
dlers’ food safety knowledge, attitudes and self-reported practices Medical Journal, 108, 937–943.
and consumers’ perceptions about street food vending in Maseru, Peltola, H. (2001). Burden of meningitis and other severe bacterial
Lesotho. British Food Journal, 123, 302–316. infections of children in Africa: implications for prevention. Clini-
Levy, K., Woster, A.P., Goldstein, R.S. & Carlton, E.J. (2016). cal Infectious Diseases, 31, 64–75.
Untangling the impacts of climate change on waterborne diseases: Peltola, H., Roine, I., Kallio, M. & Pelkonen, T. (2021). Outcome of
a systematic review of relationships between diarrheal diseases and childhood bacterial meningitis on three continents. Scientific
temperature, rainfall, flooding, and drought. Environmental Science Reports, 11, 21593.
& Technology, 50, 4905–4922. Poghossian, A., Geissler, H. & Scho€ning, M.J. (2019). Rapid
Makgopa, M. (2020). Poultry and Products Annual Report. United methods and sensors for milk quality monitoring and spoilage
States Department of Agriculture, Foreign Agriculral Service and detection. Biosensors and Bioelectronics, 140, 111272.
Global Agricultural Information Network (GAIN). https://apps. Pouillot, R., Hoelzer, K., Chen, Y. & Dennis, S.B. (2015). Listeria
fas.usda.gov/newgainapi/api/Report/DownloadReportByFileName? monocytogenes dose response revisited-incorporating adjustments
fileName=PoultryandProductsAnnual_Pretoria_SouthAfrica-Repu for variability in strain virulence and host susceptibility. Risk Anal-
blicof_09-01-2020 ysis, 35, 90–108.
Makinde, O.M., Ayeni, K.I., Sulyok, M., Krska, R., Adeleke, R.A. Reardon, T. (2015). The hidden middle: the quiet revolution in the
& Ezekiel, C.N. (2020). Microbiological safety of ready-to-eat midstream of agrifood value chains in developing countries. Oxford
foods in low- and middle-income countries: a comprehensive 10- Review of Economic Policy, 31, 45–63.
International Journal of Food Science and Technology 2023 
 2023 The Authors. International Journal of Food Science & Technology published by John Wiley & Sons Ltd
on behalf of Institute of Food, Science and Technology (IFSTTF).
Listeria monocytogenes in Africa T. Sibanda et al. 13
Reyburn, R., Kim, D.R., Emch, M., Khatib, A., von Seidlein, L. & Sun, Q., Cai, S., Cheng, J. et al. (2021). Distribution, contamination
Ali, M. (2011). Climate variability and the outbreaks of cholera in routes, and seasonal influence of persistent Listeria monocytogenes
Zanzibar, East Africa: a time series analysis. American Journal of in a commercial fresh Hypsizigus marmoreus production facility.
Tropical Medicine and Hygiene, 84, 862–869. Food Control, 127, 108118.
Ricci, A., Allende, A., Bolton, D. et al. (2018). Listeria monocyto- Taylor, B.J., Quinn, A.R. & Kataoka, A. (2019). Listeria monocyto-
genes contamination of ready-to-eat foods and the risk for human genes in low-moisture foods and ingredients. Food Control, 103,
health in the EU. EFSA Journal, 16, 5134. 153–160.
This article provides a detailed analysis of the food chain factors Thomas, J., Govender, N., McCarthy, K.M. et al. (2020). Outbreak
influencing L. monocytogenes contamination of RTE foods and inci- of listeriosis in South Africa associated with processed meat. The
dence of listeriosis in the EU. The article was critical in our conceptuali- New England Journal of Medicine, 382, 632–643.
zation of the potential factors that could influence the same in Africa. UNAIDS. (2022). Global HIV statistics. Fact Sheet 2022 https://
Rodriguez, C., Taminiau, B., Garc
ıa-Fuentes, E., Daube, G. & Kor- www.unaids.org/sites/default/files/media_asset/UNAIDS_FactSheet_
sak, N. (2021). Listeria monocytogenes dissemination in farming en.pdf
and primary production: sources, shedding and control measures. United States Food and Drug Administration (FDA) & Food Safety
Food Control, 120, 107540. and Inspection Service (FSIS). (2003). Quantitative Assessment of
Ronquest-Ross, L.-C., Vink, N. & Sigge, G.O. (2015). Food con- Relative Risk to Public Health from Foodborne Listeria Monocy-
sumption changes in South Africa since 1994. South African Jour- togenes among Selected Categories of Ready-to-Eat Foods. https://
nal of Science, 111(9/10), 1–12. www.fda.gov/food/cfsan-risk-safety-assessments/quantitative-assessment-
Rudnicka, E., Napierała, P., Podfigurna, A., Mezczekalski, B., Smo- relative-risk-public-health-foodborne-listeria-monocytogenes-among-
larczyk, R. & Grymowicz, M. (2020). The World Health Organiza- selected
tion (WHO) approach to healthy ageing. Maturitas, 139, 6–11. Unnevehr, L.J. (2022). Addressing food safety challenges in rapidly
Ryan, S.I. (2019). Consumer needs for a healthy kota sold by street developing food systems. Agricultural Economics, 53, 529–539.
vendors in the Soweto District. MSc Thesis, University of Johannesburg. Usman, U.B., Kwaga, J.K.P., Kabir, J. & Olonitola, O.S. (2016).
Saldivar, J.C., Davis, M.L., Johnson, M.G. & Ricke, S.C. (2018). Isolation and antimicrobial susceptability of Listeria monocytogenes
Listeria monocytogenes adaptation and growth at low tempera- from raw milk and milk products in northern Kaduna state, Nige-
tures: mechanisms and implications for foodborne disease. In: Food ria. Journal of Applied & Environmental Microbiology, 4, 46–54.
and Feed Safety Systems and Analysis (edited by S.C. Ricke, G.G. von Holy, A. & Makhoane, F.M. (2006). Improving street food
Atungulu, C.E. Rainwater & S.H. Park). Pp. 227–248. London: vending in South Africa: achievements and lessons learned. Inter-
Academic Press. national Journal of Food Microbiology, 111, 89–92.
Salihu, M.D., Junaidu, A.U., Manga, S.B. et al. (2008). Occurrence Waage, J., Grace, D., Fevre, E.M. et al. (2022). Changing food sys-
of Listeria monocytogenes in smoked fish in Sokoto, Nigeria. Afri- tems and infectious disease risks in low-income and middle-income
can Journal of Biotechnology, 7, 3082–3084. countries. Lancet Planet Health, 6, e760–e768.
Sampedro, F., P
erez-Rodr
ıguez, F., Servadio, J.L., Gummalla, S. & Wang, P., Asare, E., Pitzer, V.E., Dubrow, R. & Chen, K. (2022).
Hedberg, C.W. (2022). Quantitative risk assessment model to Associations between long-term drought and diarrhea among chil-
investigate the public health impact of varying Listeria monocyto- dren under five in low- and middle-income countries. Nature Com-
genes allowable levels in different food commodities: a retrospective munications, 13, 3661.
analysis. International Journal of Food Microbiology, 383, 109932. Werikhe, G., Kunyanga, C.N., Okoth, M.W. & Roba, H.G. (2019).
Schutte, C.-M., Van Der Meyden, C.H., Kakaza, M., Lockhat, Z. & Status and process analysis of koche, a traditional pastoral meat
Van Der Walt, E. (2019). Life-threatening Listeria meningitis: need product in Kenya. Pastoralism: Research, Policy and Practice, 9, 6.
for revision of south African acute bacterial meningitis treatment World Bank. (2022). Food safety in Africa: past endeavors and
guidelines. South African Medical Journal, 109, 296–298. future directions. World Bank https://doi.org/10.1596/37438
Scobie, A., Kanagarajah, S., Harris, R.J. et al. (2019). Mortality risk World Health Organization (WHO) & Food and Agriculture Organi-
factors for listeriosis – a 10 year review of non-pregnancy associ- zation of the United Nations (FAO). (2022). Listeria monocyto-
ated cases in England 2006–2015. Journal of Infection, 78, 208–214. genes in ready-to-eat (RTE) foods: attribution, characterization
Sibanda, T. & Buys, E.M. (2022). Listeria monocytogenes pathogene- and monitoring – Meeting report. Microbiological Risk Assessment
sis: the role of stress adaptation. Microorganisms, 10, 1522. Series No. 38 https://www.who.int/publications-detail-redirect/
Snyder, J., Ijumba, C., Tschirley, D. & Reardon, T. (2015). Local 9789240034969
response to the rapid rise in demand for processed and perishable Zamani, O., Pelikan, J. & Schott, J. (2021). EU exports of livestock
foods: results of an inventory of processed food products in Dar es products to West Africa: an analysis of dairy and poultry trade data.
Salaam. Policy Research Brief, 1–5. https://ageconsearch.umn.edu/ Thu€nen Working Paper, No. 162, Johann Heinrich von Thu€nen-
record/261678/files/FSPPolicyBrief42.pdf?subformat=pdfa&ver Institut, Braunschweig https://doi.org/10.3220/WP1610006088000
sion=1 Ziegler, M., Kent, D., Stephan, R. & Guldimann, C. (2019). Growth
Steyn, N.P., Labadarios, D. & Nel, J.H. (2011). Factors which influ- potential of listeria monocytogenes in twelve different types of RTE
ence the consumption of street foods and fast foods in South salads: impact of food matrix, storage temperature and storage
Africa - a national survey. Nutrition Journal, 10, 104. time. International Journal of Food Microbiology, 296, 83–92.

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on behalf of Institute of Food, Science and Technology (IFSTTF).