Parasitology Department
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Item Identification and characterisation of Mansonella perstans in the Volta Region of Ghana(2024) Opoku, M.; de Souza, D.K.Mansonella spp. have been reported to have a wide global distribution. Despite the distribution and co-occurrence with other filarial parasites like Wuchereria bancrofti, Onchocerca volvulus and Loa loa, it is given little attention. There are few surveillance programmes for assessing the distribution of mansonellosis, due to the associated mild to no symptoms experienced by infected people. However, addressing this infection is critical to the oncho cerciasis control program as current rapid diagnostic tools targeting O. volvulus have the tendency to cross react with Mansonella species. In this study we identified and character ised M. perstans from five sites in two districts in the Volta Region of Ghana and compared them to samples from other regions. Night blood smears and filter blood blots were obtained from individuals as part of a study on lymphatic filariasis. The Giemsa-stained smears were screened by microscopy for the presence of filarial parasites. Genomic DNA was extracted from blood blots from 39 individuals that were positive for M. perstans and Nested PCR tar geting the internal spacer 1 (ITS-1) was conducted. Of these, 30 were sequenced and 24 sequences were kept for further analysis. Phylogenetic analysis of 194 nucleotide positions showed no differences in the samples collected. The similarities suggests that there could be one species in this area. However, more robust studies with larger sample sizes are required to draw such conclusions. We also observed a clustering of the samples from Ghana with reference sequences from Africa and Brazil, suggesting they could be related. This study draws further attention to a neglected infection, presents the first characterisation of M. perstans in Ghana and calls for more population-based studies across different geo graphical zones to ascertain species variations and disease distribution.Item An In vitro and in silico investigation of the antitrypanosomal activities of the stem bark extracts of Anopyxis klaineana (Pierre) Engl(Heliyon, 2024) Adams, L.; Obiri-Yeboah, D.; Afiadenyo, M.; et al.African Trypanosomiasis caused by trypanosome parasites continues to be a major neglected health problem, particularly in developing countries. Current treatments are marked by serious side effects, low effectiveness, high toxicity, and drug resistance prompting the need to develop novel, safe, effective, and alternative antitrypanosomal compounds. Anopyxis klaineana is an ethnomedicinal plant used in West Africa to treat many ailments including protozoan diseases. In this study, we investigated the antitrypanosomal potential of stem bark extracts of A. klaineana through in vitro and in silico approaches. A. klaineana extracts were tested for their anti trypanosomal activities against Trypanosoma brucei parasite in vitro using Alamar blue assay. In addition, the antioxidant and cytotoxic activities were determined. LC-ESI-QTOF-MS was used to identify potential bioactive compounds present in the A. klaineana extracts. Bioactive compounds identified were subjected to molecular docking studies against Trypanosoma brucei’s trypanothione reductase (TR) and Uridine Diphosphate Galactose 4′-Epimerase (UDP). The A. klaineana extracts (methanol, hexane, chloroform, and ethyl acetate) exhibited potential anti-trypanosomal activ ities with IC50 values of 21.25 ± 0.755,4.35 ± 0.166,2.57 ± 0.153 and 22.92 ± 2.321 μg/mL respectively. Moreover, the methanolic crude extracts showed moderate cytotoxicity against HepG2 and PNT2 cells, with IC50 values of 68.0 ± 2.05 and 78.7 ± 2.63 μg/mL respectively. LC MS analysis revealed the presence of 24 bioactive compounds with 5 being druglike. Risperidone, Ranolazine, Dihydro-7-Desacetyldeoxygedunin, 6 beta-Hydroxytriamcinolone acetonide, and Dimethylmatairesinol were identified as novel potential inhibitors of TR and UDP with binding affinities of − 10.4, − 7.9, − 8.7, − 8.4 and − 7.1 kcal/mol respectively against TR and − 10.8, − 8.4, − 8.4, − 7.6 and − 8.1 respectively against UDP. This study indicates that A. klaineana has po tential antitrypanosomal properties and therefore may have the potential to be developed as a therapeutic intervention for treating African trypanosomiasis.Item Climate‑influenced vector‑borne diseases in Africa: a call to empower the next generation of African researchers for sustainable solutions(Infectious Diseases of Poverty, 2024) Obame‑Nkoghe, J.; Agossou, A.E.; Ndam, N.T.We look at the link between climate change and vector-borne diseases in low- and middle-income countries in Africa. The large endemicity and escalating threat of diseases such as malaria and arboviral diseases, intensified by climate change, disproportionately affects vulnerable communities globally. We highlight the urgency of prioritizing research and development, advocating for robust scientific inquiry to promote adaptation strategies, and the vital role that the next generation of African research leaders will play in addressing these challenges. Despite significant challenges such as funding shortages within countries, various pan-African-oriented funding bodies such as the African Academy of Sciences, the Africa Research Excellence Fund, the Wellcome Trust, the U.S. National Institutes of Health, and the Bill and Melinda Gates Foundation as well as initiatives such as the African Research Initiative for Scientific Excellence and the Pan-African Mosquito Control Association, have empowered (or are empowering) these researchers by supporting capacity building activities, including continental and global networking, skill development, mentoring, and African-led research. This article underscores the urgency of increased national investment in research, proposing the establishment of research government agencies to drive evidence-based interventions. Collaboration between governments and scientific communities, sustained by pan-African funding bodies, is crucial. Through these efforts, African nations are likely to enhance the resilience and adaptive capacity of their systems and communities by navigating these challenges effectively, fostering scientific excellence and implementing transformative solutions against climate-sensitive vector-borne diseases.Item Climate‑influenced vector‑borne diseases in Africa: a call to empower the next generation of African researchers for sustainable solutions(Infectious Diseases of Poverty, 2024) Obame-Nkoghe, J.; Agossou, A.E.; Ndam, N.T.; et.alWe look at the link between climate change and vector-borne diseases in low- and middle-income countries in Africa. The large endemicity and escalating threat of diseases such as malaria and arboviral diseases, intensified by climate change, disproportionately affects vulnerable communities globally. We highlight the urgency of prioritizing research and development, advocating for robust scientific inquiry to promote adaptation strategies, and the vital role that the next generation of African research leaders will play in addressing these challenges. Despite significant challenges such as funding shortages within countries, various pan-African-oriented funding bodies such as the African Academy of Sciences, the Africa Research Excellence Fund, the Wellcome Trust, the U.S. National Institutes of Health, and the Bill and Melinda Gates Foundation as well as initiatives such as the African Research Initiative for Scientific Excellence and the Pan-African Mosquito Control Association, have empowered (or are empowering) these researchers by supporting capacity building activities, including continental and global networking, skill development, mentoring, and African-led research. This article underscores the urgency of increased national investment in research, proposing the establishment of research government agencies to drive evidence-based interventions. Collaboration between governments and scientific communities, sustained by pan-African funding bodies, is crucial. Through these efforts, African nations are likely to enhance the resilience and adaptive capacity of their systems and communities by navigating these challenges effectively, fostering scientific excellence and implementing transformative solutions against climate-sensitive vector-borne diseases.Item Spatial and Seasonal Patterns of Tick Infestations in Kassena-Nankana Livestock(Veterinary Medicine International, 2024) Addo, S.O.; Bentil, R.E.; Ansah-Owusu, J.; Dunford, J.C.; et al.The ability of ticks to adapt to different ecological zones, coupled with the spread of infectious pathogens, negatively affects livestock production and thus, there is a need for better control strategies. However, control measures within a geographical region can only be effective if there is available information on tick population dynamics and ecology. This study focused on ticks infesting livestock in the Kassena-Nankana Districts of the Upper East Region of Ghana. The ticks were morphologically identified, and variables such as season, animal host, and predilection sites were recorded, and the data were analyzed using STATA version 13. Out of 448 livestock examined, tick infestation in cattle was 78.60%, followed by sheep (25%) and goats (5.88%). A total of 1,550 ticks, including nymphs (303) and adults (1,247) were collected. Adult ticks were found to be significantly associated with season (p < 0.001), with a high burden in the wet season. The nymph burden and body parts of livestock hosts were significantly associated with more nymphs collected from male animals than females (p < 0.001). Tree genera of ticks: Amblyomma (62.97%), Hyalomma (18.71%), and Rhipicephalus (18.32%) were morphologically identified with the most predominant tick species recorded as Amblyomma variegatum (62.97%). Mature A. variegatum was sampled primarily in the wet season, with their predilection site as the udder/scrotum (p < 0.001). However, adult Hyalomma truncatum was observed to have a significant association with the anal region (p < 0.001). Findings from this study are essential for formulating tick control measures to prevent the spread of infectious pathogens.Item Two promising candidates for paratransgenesis, Elizabethkingia and Asaia, increase in both sexes of Anopheles gambiae mosquitoes after feeding(Malaria Journal, 2024) Egyirifa, R.K.; Akorli, J.Background The male mosquito microbiome may be important for identifying ideal candidates for disease control. Among other criteria, mosquito-associated symbionts that have high localization in both male and female mosquitoes and are transmissible through both vertical and sexual routes are desirable. However, mosquito microbiome Studies have mainly been female-focused. In this study, the microbiota of male and female Anopheles gambiae sensu lato (s.l.) were compared to identify shared or unique bacteria. Methods Late larval instars of Anopheles mosquitoes were collected from the field and raised to adults. Equal numbers of males and females of 1-day-old non-sugar-fed, 4-5-day-old sugar-fed and post-blood-fed females randomly selected for whole-body analyses of bacteria 16S rRNA. Results Results revealed that male and female mosquitoes generally share similar microbiota, except when females were blood-fed. Compared to newly emerged unfed mosquitoes, feeding on sugar and/or blood increased variability in microbial composition (⍺-diversity), with a higher disparity among females (39% P = 0.01) than in males (29% P=0.03). Elizabethkingia meningoseptica and Asaia siamensis were common discriminants between feeding statuses in both males and females. While E. meningoseptica was particularly associated with sugar-fed mosquitoes, of both sexes and sustained after blood feeding in females, A. siamensis was also increased in sugar-fed mosquitoes but decreased significantly in blood-fed females (LDA score > 4.0, P<0.05). Among males, A. siamensis did not differ significantly after sugar meals. Conclusions Results indicate the opportunities for stable infection in mosquitoes should these species be used in bacteria-mediated disease control. Further studies are recommended to investigate possible host-specifc tissue tropism of bacteria species, which will inform the selection of the most appropriate microbes for effective transmission-blocking strategies.Item First Whole Genome Sequencing of Crimean–Congo Hemorrhagic Fever Virus (CCHFV) in Tick Species within Ghana(Transboundary and Emerging Diseases, 2023) Bentil, R.E.; Addo, S.O.; Dadzie, S.K.; et al.Crimean–Congo hemorrhagic fever (CCHF) is a serious viral zoonotic disease spread by ticks and caused by the Crimean–Congo hemorrhagic fever virus (CCHFV). The emergence and reemergence of CCHF in various nations in the Eastern Mediterranean Region over the last decade have shown a growing risk of the disease spreading to new areas, especially in population-dense and livestock trade-dominant areas. There is a lack of updated information on the risk of CCHFV in the Greater Accra and Upper East Regions of Ghana. Due to the paucity of available data, this study sought to identify the tick species diversity in Ghana and to ascertain the CCHFV strains they may carry. A total of 705 ticks were collected from 188 cattle and 11 horses and morphologically identified. Three tick genera (Hyalomma, Amblyomma, and Rhipicephalus) were observed, with the predominant species being Hyalomma rufipes (n = 290, 41.1%). The CCHFV infection rates of 0.78%, 0.69%, and 0.64% were recorded in Hyalomma truncatum, H. rufipes, and Amblyomma variegatum, respectively. No infection was detected in the Rhipicephalus species. Furthermore, a strain was successfully recovered using next-generation sequencing. The strain belongs to genotype 3 and shared 98.9% nucleotide identity with DQ211641_Mauritania_1984 and MF287636_Spain_2016. Findings from this study suggest the possible importation of the virus into the country through trade, and potentially, a public health threat to humans who may have primary contact with livestockItem Entomological risk assessment for transmission of arboviral diseases by Aedes mosquitoes in a domestic and forest site in Accra, Ghana(PLOS ONE, 2023) Akyea-Bob, N.E.; Akorli, J.; Opoku, M.; et al.Dengue, Zika and chikungunya are Aedes-borne viral diseases that have become great global health concerns in the past years. Several countries in Africa have reported out breaks of these diseases and despite Ghana sharing borders with some of these coun tries, such outbreaks are yet to be detected. Viral RNA and antibodies against dengue serotype-2 have recently been reported among individuals in some localities in the regional capital of Ghana. This is an indication of a possible silent transmission ongoing in the population. This study, therefore, investigated the entomological transmission risk of dengue, Zika and chikungunya viruses in a forest and domestic population in the Greater Accra Region, Ghana. All stages of the Aedes mosquito (egg, larvae, pupae and adults) were collected around homes and in the forest area for estimation of risk indices. All eggs were hatched and reared to larvae or adults for morphological identification together with larvae and adults collected from the field. The forest population had higher species richness with 7 Aedes species. The predominant species of Aedes mosquitoes identified from both sites was Aedes aegypti (98%). Aedes albopictus, an important arbo virus vector, was identified only in the peri-domestic population at a prevalence of 1.5%, significantly higher than previously reported. All risk indices were above the WHO thresh old except the House Index for the domestic site which was moderate (19.8). The forest population recorded higher Positive Ovitrap (34.2% vs 26.6%) and Container (67.9% vs 36.8%) Indices than the peri-domestic population. Although none of the mosquito pools showed the presence of dengue, chikungunya or Zika viruses, all entomological risk indi cators showed that both sites had a high potential arboviral disease transmission risk should any of these viruses be introduced. Continuous surveillance is recommended in these and other sites in the Metropolis to properly map transmission risk areas to inform outbreak preparedness strategies.Item Antimicrobial use of patients with sexually transmitted infection symptoms prior to presentation at five health facilities in Southern Ghana(Antimicrobial Resistance & Infection Control, 2023) Attram, N.; Dela, H.; Behene, E.; et al.Background Unregulated and inappropriate antimicrobial use are major contributors to the evolution of antimicrobial resistance worldwide. It is important to monitor and collect data on the use of antibiotics at health facilities and in the general population in order to support antimicrobial stewardship programs. Methods As part of a gonorrhea surveillance study that was conducted from June 2012 to Jan 2018, we administered a questionnaire to elicit information on the types of antimicrobials used by individuals to treat symptoms of a gonorrhea infection prior to presenting at five health facilities in Southern Ghana. Results Almost one-third (383/1,349; 28%) of study participants admitted taking one or more antimicrobial types before hospital presentation, while 138/383 (36%) of those who took antimicrobials could not remember what they ingested. A greater percentage of individuals who reported prior antimicrobial use before presentation at a health facility tested positive for gonorrhea by NAAT (30%), in contrast to 24% for those without prior treatment (p=0.004). Penicillin and its derivatives, as well as ciprofloxacin and doxycycline, were the most used, while a few individuals reported taking drugs such as kanamycin and rifampin. Males were more likely than females to take an antimicrobial prior to attending a health center. Conclusion In order to curb excessive and inappropriate antimicrobial use, antibiotics used by patients before presenting at hospitals ought to be investigated by healthcare providers. It is recommended that health professionals receive continuing education on the consequences of unregulated antimicrobial use.Item Design of Inhibitors That Target the Menin–Mixed-Lineage Leukemia Interaction(Computation, 2023) Arthur, M.N.; Bebla, K.; Kwofie, S.K.; et al.The prognosis of mixed-lineage leukemia (MLL) has remained a significant health concern. especially for infants. The minimal treatments available for this aggressive type of leukemia has been an ongoing problem. Chromosomal translocations of the KMT2A gene are known as MLL. which expresses MLL fusion proteins. A protein called menin is an important oncogenic cofactor for these MLL fusion proteins, thus providing a new avenue for treatments against this subset of acute leukemias. In this study, we report results using structure-based drug design (SBDD) approach to discovering potential novel MLL-mediated leukemia inhibitors from natural products against menin. The three-dimensional (3D) protein model was derived from Protein Databank (Protein ID: 4GQ4), and EasyModeller 4.0 and I-TASSER were used to fix missing residues during rebuilding. Out of the ten protein models generated (five from EasyModeller and I-TASSER each), One model was selected. The selected model demonstrated the most reasonable quality and had 75.5% of residues in the most favored regions, 18.3% of residues in additionally allowed regions, and 3.3% of residues in generously allowed regions, and 2.9% of residues in disallowed regions. A ligand library containing 25,131 ligands from a Chinese database was virtually screened using AutoDock Vina, in addition to three known menin inhibitors. The top 10 compounds, including ZINC000103526876, ZINC000095913861, ZINC000095912705, ZINC000085530497, ZINC000095912718, ZINC000070451048, ZINC000085530488, ZINC000095912706, ZINC000103580868, and ZINC000103584057 had binding energies of −11.0, −10.7, −10.6, −10.2, −10.2, −9.9, −9.9, −9.9, −9.9, and −9.9 kcal/mol, respectively. To confirm the stability of the menin-ligand complexes and the binding mechanisms, molecular dynamics simulations, including molecular mechanics and Poisson-Boltzmann surface area (MM/PBSA) computations were performed. The amino acid residues that were found to be potentially crucial in ligand binding included Phe243, Met283, Cys246, Tyr281, Ala247, Ser160, Asn287, Asp185, Ser183, Tyr328, Asn249, His186, Leu182, Ile248, and Pro250. MI-2-2 and PubChem CIDs 71777742 and 36294 were shown to possess anti-menin properties; thus, this justifies a need to experimentally determine the activity of the identified compounds. The compounds identified herein were found to have good pharmacological profiles and negligible toxicity. Additionally, these compounds were predicted as antileukemic, antineoplastic, chemopreventive, and apoptotic agents. The 10 natural compounds can be further explored as potential novel agents for the effective treatment of MLL-mediated leukemia.