Research Articles

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A research article reports the results of original research, assesses its contribution to the body of knowledge in a given area, and is published in a peer-reviewed scholarly journal. The faculty publications through published and on-going articles/researches are captured in this community

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    Assessment of Patterns of Climate Variables and Malaria Cases in Two Ecological Zones of Ghana
    (Open Journal of Ecology, 2014) Klutse, N.A.B.; Aboagye-Antwi, F.; Owusu, K.; Ntiamoa-Baidu, Y.
    Climate change is projected to impact human health, particularly incidence of water related and vector borne diseases, such as malaria. A better understanding of the relationship between rainfall patterns and malaria cases is thus required for effective climate change adaptation strategies involving planning and implementation of appropriate disease control interventions. We analyzed climatic data and reported cases of malaria spanning a period of eight years (2001 to 2008) from two ecological zones in Ghana (Ejura and Winneba in the transition and coastal savannah zones respectively) to determine the association between malaria cases, and temperature and rainfall patterns and the potential effects of climate change on malaria epidemiological trends. Monthly peaks of malaria caseloads lagged behind monthly rainfall peaks. Correlation between malaria caseloads and rainfall intensity, and minimum temperature were generally weak at both sites. Lag correlations of up to four months yielded better agreement between the variables, especially at Ejura where a two-month lag between malaria caseloads and rainfall was significantly high but negatively correlated (r = −0.72; p value < 0.05). Mean monthly maximum temperature and monthly malaria caseloads at Ejura showed a strong negative correlation at zero month lag (r = −0.70, p value < 0.05), with a similar, but weaker relationship at Winneba, (r = −0.51). On the other hand, a positive significant correlation (r = 0.68, p value < 0.05) between malaria caseloads and maximum temperature was observed for Ejura at a four-month lag, while Winneba showed a strong correlation (r = 0.70; p value < 0.05) between the parameters at a two-month lag. The results suggest maximum temperature as a better predictor of malaria trends than minimum temperature or precipitation, particularly in the transition zone. Climate change effects on malaria caseloads seem multi-factorial. For effective malaria control, interventions could be synchronized
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    Musings on malaria morbidity and mortality after the new Mosquirix® vaccine.
    (Ghana Med J, 2019-06-26) Sackey, A.H.
    There are some facts relating to the new malaria vaccine (Mosquirix® or RTS,S/AS01) recently introduced in Ghana, which need to be more widely known. Contrary to expectations based on mathematical modelling and on the vaccine’s effect on clinical malaria and severe malaria, mortality was not reduced in children receiving the Mosquirix® vaccine in the phase 3 trial.1 This (surprising) result has been attributed to the fact that mortality was reduced in both the vaccinated and unvaccinated children due to better implementation of malaria control measures such as use of bed nets and prompt treatment of malaria.2 The startling implication of this finding is that when the existing malaria control measures are implemented more effectively, the vaccine in its current form does not offer any measurable mortality advantages. This means that if there were a willingness to implement malaria control measures intensively, there would be no need to expose our children to the unknown effects of a new vaccine.
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    Plasma mEV levels in Ghanain malaria patients with low parasitaemia are higher than those of healthy controls, raising the potential for parasite markers in mEVs as diagnostic targets
    (Journal of Extracellular Vesicles, 2019-12-18) Antwi-Baffour, S.; Malibha-Pinchbeck, M.; Stratton, D.; Jorfi, S.; Lange, S.; Inal, J.
    This study sought to measure medium-sized extracellular vesicles (mEVs) in plasma, when patients have low Plasmodium falciparum early in infection. We aimed to define the relationship between plasma mEVs and: (i) parasitaemia, (ii) period from onset of malaria symptoms until seeking medical care (patient delay, PD), (iii) age and (iv) gender. In this cross-sectional study, n = 434 patients were analysed and Nanosight Tracking Analysis (NTA) used to quantify mEVs (vesicles of 150–500 nm diameter, isolated at 15,000 × g, β-tubulin-positive and staining for annexin V, but weak or negative for CD81). Overall plasma mEV levels (1.69 × 1010 mEVs mL−1) were 2.3-fold higher than for uninfected controls (0.51 × 1010 mEVs mL−1). Divided into four age groups, we found a bimodal distribution with 2.5- and 2.1-fold higher mEVs in infected children (<11 years old [yo]) (median:2.11 × 1010 mEVs mL−1) and the elderly (>45 yo) (median:1.92 × 1010 mEVs mL−1), respectively, compared to uninfected controls; parasite density varied similarly with age groups. There was a positive association between mEVs and parasite density (r = 0.587, p < 0.0001) and mEVs were strongly associated with PD (r = 0.919, p < 0.0001), but gender had no effect on plasma mEV levels (p = 0.667). Parasite density was also exponentially related to patient delay. Gender (p = 0.667) had no effect on plasma mEV levels. During periods of low parasitaemia (PD = 72h), mEVs were 0.93-fold greater than in uninfected controls. As 75% (49/65) of patients had low parasitaemia levels (20–500 parasites μL−1), close to the detection limits of microscopy of Giemsa-stained thick blood films (5–150 parasites μL−1), mEV quantification by NTA could potentially have early diagnostic value, and raises the potential of Pf markers in mEVs as early diagnostic targets
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    Understanding the gap between access and use: a qualitative study on barriers and facilitators to insecticide‑treated net use in Ghana
    (Malaria Journal, 2019-12-12) Ahorlu, C.S.; Adongo, P.; Koenker, H.; Zigirumugabe, S.; Sika‑Bright, S.; Koka, E.; Tabong, P.T-N.
    Background: Mass and continuous distribution channels have significantly increased access to insecticide-treated nets (ITNs) in Ghana since 2000. Despite these gains, a large gap remains between ITN access and use. Methods: A qualitative research study was carried out to explore the individual and contextual factors influencing ITN use among those with access in three sites in Ghana. Eighteen focus group discussions, and free listing and ranking activities were carried out with 174 participants; seven of those participants were selected for in-depth case study. Focus group discussions and case study interviews were audio-recorded, transcribed verbatim, and analysed thematically. Results: ITN use, as described by study participants, was not binary; it varied throughout the night, across seasons, and over time. Heat was the most commonly cited barrier to consistent ITN use and contributed to low reported ITN use during the dry season. Barriers to ITN use throughout the year included skin irritation; lack of airflow in the sleeping space; and, in some cases, a lack of information on the connection between the use of ITNs and malaria prevention. Falling ill or losing a loved one to malaria was the most powerful motivator for consistent ITN use. Participants also discussed developing a habit of ITN use and the economic benefit of prevention over treatment as facilitating factors. Participants reported gender differences in ITN use, noting that men were more likely than women and children to stay outdoors late at night and more likely to sleep outdoors without an ITN. Conclusion: The study results suggest the greatest gains in ITN use among those with access could be made by promoting consistent use throughout the year among occasional and seasonal users. Opportunities for improving communication messages, such as increasing the time ITNs are aired before first use, as well as structural approaches to enhance the usability of ITNs in challenging contexts, such as promoting solutions for outdoor ITN use, were identified from this work. The information from this study can be used to inform social and behaviour change messaging and innovative approaches to closing the ITN use gap in Ghana.
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    Factors influencing adherence to the new intermittent preventive treatment of malaria in pregnancy policy in Keta District of the Volta region, Ghana
    (BMC Pregnancy and Childbirth, 2019-11-20) Vandy, A.O.; Peprah, N.Y.; Jerela, Y.; Titiati, P.; Manu, A.; Akamah, J.; Maya, E.T.; Torpey, K.
    Background: About 25% of pregnant women in malaria-endemic areas are infected with malaria and this accounts for about 15% of maternal deaths globally. Intermittent preventive treatment in pregnancy with sulfadoxinepyrimethamine (IPTp-SP) is one of the main strategies for prevention of malaria in pregnancy. A new recommendation was made by the World Health Organization (WHO) that at least three doses of IPTp-SP should be administered before delivery. This study sought to determine the factors influencing adherence to the new IPTp-SP policy in Keta District, Volta region, Ghana. Methods: A cross-sectional quantitative study among 375 nursing mothers at four selected health facilities in Keta district, Ghana was conducted using a structured questionnaire to interview participants. Sampling proportionate to the size of facility was used to determine the number of nursing mothers from each facility based on the caseload. For each facility systematic random sampling was used to select eligible nursing mothers. Data was analyzed using STATA 15. Chi-square was used to test bivariate association between categorical variables and adherence. Logistic regression analysis was used to examine sociodemographic, individual and institutional factors influencing adherence to IPTp-SP. Result: About 82.1% of participants adhered to the WHO policy recommendations of at least three doses of IPTp- SP. However, only 17.1% received Ghana’s five dose coverage recommendation. The proportion of IPTp-SP coverage for IPTp1 was 98.9%; IPTp2 95.5%; IPTp3 80.8%; IPTp4 39.5%; IPTp5 17.1%. Conclusion: Adherence to IPTp-SP was satisfactory according to WHO’s policy recommendation, however, majority of the participants had less than the five doses recommended in Ghana. Number of Antenatal Care (ANC) visits and knowledge of malaria were the main determinants of adherence to IPTp-SP.
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    Targeted Next Generation Sequencing for malaria research in Africa: current status and outlook
    (Malaria Journal, 2019-09-23) Ghansah, A.; Kamau, E.; Amambua‑Ngwa, A.; Ishengoma, D.S.; Maiga‑Ascofare, O.; Amenga‑Etego, L.; Deme, A.; Yavo, W.; Randrianarivelojosia, M.; Ochola‑Oyier, L.I.; Helegbe, G.K.; Bailey, J.; Alifrangis, M.; Djimde, A.
    Targeted Next Generation Sequencing (TNGS) is an efficient and economical Next Generation Sequencing (NGS) platform and the preferred choice when specific genomic regions are of interest. So far, only institutions located in middle and high-income countries have developed and implemented the technology, however, the efficiency and cost savings, as opposed to more traditional sequencing methodologies (e.g. Sanger sequencing) make the approach potentially well suited for resource-constrained regions as well. In April 2018, scientists from the Plasmodium Diversity Network Africa (PDNA) and collaborators met during the 7th Pan African Multilateral Initiative of Malaria (MIM) conference held in Dakar, Senegal to explore the feasibility of applying TNGS to genetic studies and malaria surveillance in Africa. The group of scientists reviewed the current experience with TNGS platforms in sub-Saharan Africa (SSA) and identified potential roles the technology might play to accelerate malaria research, scientific discoveries and improved public health in SSA. Research funding, infrastructure and human resources were highlighted as challenges that will have to be mitigated to enable African scientists to drive the implementation of TNGS in SSA. Current roles of important stakeholders and strategies to strengthen existing networks to effectively harness this powerful technology for malaria research of public health importance were discussed
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    Reversible Binocular Visual Loss in Temporal Association with Artesunate-Amodiaquine Treatment in a Child on Mefloquine Chemoprophylaxis
    (Ghana medical journal, 2012-09) Adjei, G.O.; Adabayeri, V.M.; Annobil, S.H.
    A case of an acute reversible visual loss in a 10-yearold child who was on mefloquine prophylaxis, and was treated with artesunate-amodiaquine for an acute febrile illness diagnosed clinically as uncomplicated malaria, is reported. On admission the patient could not perceive light and had bilateral papilloedema. She was treated with dexamethasone and recovered her sight gradually over a 21-day period. There has been no previous report to our knowledge, of an association between acute visual loss and mefloquine, amodiaquine, or artesunate in the published literature, even though mefloquine is associated with blurring of vision, and antimalarials of the quinoline class have been associated with retinopathy (during long term use). While causality is difficult to ascribe in this case, it may be prudent to avoid the use of quinoline-based antimalarials for treating acute malaria in travelers taking mefloquine prophylaxis, because information on the safety of concurrent use of artemisinin combination therapies and mefloquine, or other recommended prophylactic regimens, is limited.
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    Malaria vaccine deployment in Africa: focus on Ghana
    (Ghana medical journal, 2019-06-02) Koram, K.A.; Asante, K.P.; Binka, F.N.
    The announcement by the Ghana Health Service /Ministry of Health at the beginning of May to begin the pilot implementation of the malaria vaccine – RTS,S/AS01 (Mosquirix®) – manufactured by GSK Biologicals was greeted with rumours about conspiracy theories of secret agenda to depopulate Africa through the use of vaccines and all the other stories that are often propagated by the anti vaxxers. This was not unlike the fear and panic spread throughout the country that prevented investigators from conducting clinical trials on new vaccines against the Ebola virus disease a few years ago.
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    RTS,S/AS01E immunization increases antibody responses to vaccine-unrelated Plasmodium falciparum antigens associated with protection against clinical malaria in African children: A case-control study
    (BMC Medicine, 2019-08-14) Gyan, B.; Dobaño, C.; Ubillos, I.; Jairoce, C.; Vidal, M.; Jiménez, A.; Santano, R.; Dosoo, D.; Nhabomba, A.J.; Ayestaran, A.; Aguilar, R.; Williams, N.A.; Díez-Padrisa, N.; Lanar, D.; Chauhan, V.; Chitnis, C.; Dutta, S.; Gaur, D.; Angov, E.; Asante, K.P.; Owusu-Agyei, S.; Valim, C.; Gamain, B.; Coppel, R.L.; Cavanagh, D.; Beeson, J.G.; Campo, J.J.; Moncunill, G.
    Background: Vaccination and naturally acquired immunity against microbial pathogens may have complex interactions that influence disease outcomes. To date, only vaccine-specific immune responses have routinely been investigated in malaria vaccine trials conducted in endemic areas. We hypothesized that RTS,S/A01E immunization affects acquisition of antibodies to Plasmodium falciparum antigens not included in the vaccine and that such responses have an impact on overall malaria protective immunity. Methods: We evaluated IgM and IgG responses to 38 P. falciparum proteins putatively involved in naturally acquired immunity to malaria in 195 young children participating in a case-control study nested within the African phase 3 clinical trial of RTS,S/AS01E (MAL055 NCT00866619) in two sites of different transmission intensity (Kintampo high and Manhiça moderate/low). We measured antibody levels by quantitative suspension array technology and applied regression models, multimarker analysis, and machine learning techniques to analyze factors affecting their levels and correlates of protection. Results: RTS,S/AS01E immunization decreased antibody responses to parasite antigens considered as markers of exposure (MSP142, AMA1) and levels correlated with risk of clinical malaria over 1-year follow-up. In addition, we show for the first time that RTS,S vaccination increased IgG levels to a specific group of pre-erythrocytic and blood-stage antigens (MSP5, MSP1 block 2, RH4.2, EBA140, and SSP2/TRAP) which levels correlated with protection against clinical malaria (odds ratio [95% confidence interval] 0.53 [0.3–0.93], p = 0.03, for MSP1; 0.52 [0.26–0.98], p = 0.05, for SSP2) in multivariable logistic regression analysesConclusions: Increased antibody responses to specific P. falciparum antigens in subjects immunized with this partially efficacious vaccine upon natural infection may contribute to overall protective immunity against malaria. Inclusion of such antigens in multivalent constructs could result in more efficacious second-generation multistage vaccines.
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    The Release of Genetically Engineered Mosquitoes in Burkina Faso: Bioeconomy of Science, Public Engagement and Trust in Medicine
    (African Studies Review, 2019-06-08) Ganle, J.K.; Beisel, U.
    The Release of Genetically Engineered Mosquitoes in Burkina Faso: Bioeconomy of Science, Public Engagement and Trust in Medicine - Volume 62 Issue 3 - Uli Beisel, John Kuumuori Ganle