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Item Plasmodium Falciparum Pfs47 Haplotype Compatibility to Anopheles Gambiae in Kisumu, a Malaria-Endemic Region of Kenya(Scientific Reports, 2025-02) Onyango, Shirley A.; Machani, Maxwell G.; Ochwedo, Kevin O.; Oriango, Robin M.; Lee, Ming-Chieh; Kokwaro, Elizabeth; Afrane, Yaw A.; Githeko, Andrew K.; Zhong, Daibin; Yan, GuiyunInsecticide resistance and outdoor transmission have reduced the effectiveness of existing malaria transmission prevention strategies. As a result, targeted approaches to support continuing malaria control, such as transmission-blocking vaccines, are required. Cross-sectional mass blood screening in children between 5 and 15 years was conducted in Chulaimbo, Kisumu, during the dry and wet seasons in 2018 and 2019. Plasmodium falciparum gametocyte carriers were identified by Microscopy. Subsequently, carriers were used to feed colony bred Anopheles gambiae females in serum replacement and whole blood membrane feeding experiments. The infection prevalence was 19.7% (95% Cl 0.003–0.007) with 95% of the infections being caused by P. falciparum. Of all confirmed P. falciparum infections, 16.9% were gametocytes. Thirty-seven paired experiments showed infection rates of 0.9% and 0.5% in the serum replacement and whole blood experiments, respectively, with no significant difference (P=0.738). Six Pfs47 haplotypes were identified from 24 sequenced infectious blood samples: Hap_1 (E27D and L240I), Hap_2 (S98T); Hap_3 (E27D); Hap_4 (L240I); Hap_5 (E188D); and Hap_6 without mutations. Haplotype 4 had the highest frequency of 29.2% followed by Hap_3 and Hap_6 at 20.8% each then Hap_1 with a frequency of 16.7%, whereas Hap_5 and Hap_2 had frequencies of 8.3% and 4.2% respectively. Varying frequencies of Pfs47 haplotypes observed from genetically heterogeneous parasite populations in endemic regions illuminates vector compatibility to refracting P. falciparum using the hypothesized lock and key analogy. This acts as a bottleneck that increases the frequency of P. falciparum haplotypes that escape elimination by vector immune responses. The interaction can be used as a potential target for transmission blocking through a refractory host.Item A Review of fish value-added products in Kenya: Current status, challenges and areas for improvement(SUSTAINABLE AQUATIC RESEARCH, 2025-03) Kyule, Domitila; Munguti, Jonathan; Muthoka, Mavindu; Opiyo, Mary A.; Abwao, Jacob; Maundu,AnneFish products are essential to Kenya’s economy and nutrition, yet their high perishability limits their accessibility and export potential. Developing fish value-added products—such as fish samosas, sausages, fillets, and powders— presents a promising solution, potentially enhancing resource utilization, reducing waste, and expanding markets. Despite contributing approximately 0.6% to Kenya’s GDP and supporting over 1.2 million livelihoods, the fish sector remains underutilized due to limited value addition. This review provides the first comprehensive synthesis of Kenya’s fish value-added sector—bridging fragmented insights on product types, technologies, economic potential, and policy gaps—offering a practical foundation for informed decision-making and investment. Key products included in this review are samosas, fillets, sausages, fish balls, smoked fish, fish oils, burgers, and soups, alongside primary processing techniques such as improved smoking kilns, Mama Karanga boxes, chilling, and freezing. The review followed the PRISMA framework to systematically identify, screen, and analyze relevant peer-reviewed articles, grey literature, and government reports. Out of 625 initially identified documents, 64 high-quality sources were included in the final synthesis. Results show that value-added products such as fish fingers, sausages, and samosas are increasingly preferred due to their profitability, consumer appeal, and potential to reduce post-harvest losses. However, their development is hindered by weak market linkages, poor regulatory and quality controls, limited access to technology, inadequate policy support, and limited awareness among consumers and producers. Increasing consumer and producer awareness through training, improved market information systems, and accessible financing options could stimulate growth of the fish value addition sector. This paper’s insights underscore the need for strategic interventions to unlock the potential of Kenya’s fish value-added sector, fostering livelihood enhancement and food security. Implementation of targeted programs and policies can transform the fisheries and aquaculture sector into a robust contributor to the country’s economic resilience and community well-being.Item Soluble Leishmania Antigens Plus Pristane Adjuvant Induce Partial Cross-protection Against Leishmaniasis in BALB/c mice(2025-04) Wabwoba, Byrum; Matoke-Muhia, Damaris; Ingonga, Johnston; Lusweti, Japheth; Gicheru, MichaelLeishmaniasis is a vector-borne parasitic disease of global concern. The disease is currently controlled by vector management and treatment of infected individuals as there is no approved vaccine. This study evaluated the safety, immunopotency and cross-immunity in BALB/c mice vaccinated with soluble Leishmania major or L. donovani antigens co-administered with 2,6,10,14-tetramethylpentadecane (pristane) and challenged with either L major or L.donovani virulent parasites. Safety was assessed by establishing dose-dependent blood-cell and platelet counts at 28 days post-injection, immunopotency was determined by measurement of interferon-gamma (IFN-ɣ) and interleukin 10 (IL-10) production, and disease progression by measurement either footpad lesion and parasite load in case of L.major challenge or spleen parasite loads for L.donovani challenge at 45 days post-infection. There was no significant effect by pristane on blood cell and platelet counts, indicating that at 20ug/mL, pristane was safe to use as an adjuvant in mice. Mice vaccinated with soluble L. donovani antigens plus pristane and challenged with L. major had smaller infected footpad lesions and lower parasite loads compared to BCG-vaccinated and unvaccinated mice. Similarly, mice vaccinated with soluble L. major antigens plus pristane and challenged with L. donovani had lower splenic parasite loads than unvaccinated mice. These corresponded with increased production of IFN-ɣ and suppressed production of IL-10 in each of the vaccinated groups, suggesting an up-regulated protective T helper 1 (Th1) response. The results indicated that vaccination of BALB/c mice with pristane adjuvant co-administered with soluble Leishmania antigens promotes Th1 response that confers partial cross-immunity against infection with heterologous Leishmania parasites. Further investigations on the safety of pristane in the longer term as well as other factors other than Th1 cytokines production up-regulation that may influence cross-protection in Leishmania infections need to be investigatedItem Apparent Protein Digestibility and Growth Performance of Nile Tilapia (Oreochromis niloticus L.) Fed on Sunflower and Cotton Seed Meal as Substitutes for Freshwater Shrimp Meal (Caridina nilotica)(Wiley, 2024) Maundu,Anne; Munguti,Jonathan; Sharma,Rekha; Kasoz,Nasser; Liti,David; Mavindu, Muthoka; Kirimi,James; Mutiso,Joshuaish feed is critical in aquaculture production, accounting for over 60% of operational costs, with protein being the most expensivecomponent. Traditionally, fish meal (FM) has been the primary protein source. However, due to declining capture fisheries andhigh demand, FM has become scarce and costly, necessitating the search for alternative, low-cost, and nutritionally balancedprotein sources. A 180-day feeding experiment was conducted to evaluate the effects of replacing FM with a combination ofcottonseed and sunflower meal (SFM) in Nile tilapia diets on growth performance, protein digestibility, and economic returns.Freshwater shrimp meal was replaced at 25%, 50%, 75%, and 100% (diets D1, D2, D3, and D4) and compared to the control diet(D0) containing only FM. Monosex Nile tilapia fingerlings (25 Æ 0.01 g) were allocated to 15 cages within an 800 m 2 earthen pond.Fish on diets D0 and D1 showed superior growth performance metrics, including final mean body weight, weight gain, daily weightgain, specific growth rate, feed conversion ratio, and survival rate (p>0:05), compared to diets D2, D3, and D4. Growth perfor-mance declined significantly with increasing levels of the plant protein mixture (p<0:05). Diet D0 had the highest apparent proteindigestibility, while D4 had the lowest. Cost-benefit analysis revealed that diet D0 had the highest production cost, followed by dietsD1, D2, D3, and D4, with no significant cost difference between D0 and D1 (p>0:05). Thus, the plant protein mixture caneffectively replace FM at a 25% inclusion level in Nile tilapia diets.Item Negative Effects by Mineral Accretion Technique on the Heat Resilience, Growth and Recruitment of Corals(Plos One, 2024-12) Knoester, Ewout Geerten; Sanders, Richard; Durden, Daisy; Masiga, Bulisa O.; Murk, Albertinka J.; Osinga, RonaldRestoration and artificial reefs can assist the recovery of degraded reefs but are limited in scalability and climate resilience. The Mineral Accretion Technique (MAT) subjects metal artificial reefs to a low-voltage electrical current, thereby creating a calcium-carbonate coating. It has been suggested that corals on MAT structures experience enhanced health and growth. However, prior studies report conflicting results potentially due to different conditions, species and approaches used. We investigated how MAT influences the bleaching resilience, condition and growth of four coral species and natural coral recruitment in Kenya. Coral fragments were outplanted on charged iron tables using commonly-applied settings (6 V; 0.84 A m-2). After one month, when all tables had acquired a calcium-carbonate coating, half of the tables were taken off electricity to serve as controls. Both treatments (MAT and Control) were monitored on coral brightness, condition (live tissue cover), growth and natural recruitment for one year, during which a marine heatwave occurred. Coral bleaching was significantly more severe on MAT for all studied species. For three species, coral condition dropped sharply during the heatwave and this decline was faster and more severe on MAT. Coral growth was reduced during the heatwave for all corals and remained low for one species on MAT. After one year, the Control harboured 34 coral recruits, whereas none were found on MAT. Thus, while MAT can be useful to prevent corrosion of metal artificial reefs, we do not recommend MAT as reported here to improve coral growth, condition, heat resilience or recruitment.Item A Survey of Knowledge and Attitudes towards Antibiotic Use and Resistance among Teachers in the Republic of Kenya: Implications for Using Teachers in Raising Public Awareness of Rational Antibiotic Use in School Communities(Plos One, 2024-12) Mutua, Patrick M.; Mutiso, Joshua; Gicheru, Michael M.Background Antimicrobial resistance is a significant public health threat. In Kenya, schools are targeted for public education to promote knowledge and attitudes towards the proper use of antimicrobials. However, there are limited studies that have investigated teachers’ knowledge and attitudes on antibiotic use. Methods We conducted an online survey from December 2023 to January 2024 which included 608 primary and secondary school teachers, representing a response rate of 93% of the estimated sample size of 653 teachers. Data on the respondents’ antibiotic knowledge score (seventeen questions) and attitude score (eleven questions) were analysed using IBM SPSS (Version 27). A binary logistic regression model was applied to analyze predicators of adequate knowledge and attitude on antibiotics. Results The average knowledge score for antibiotic use was 9.2 out of 17. Among the sampled teachers, 82% had not received public awareness information on proper antibiotic use. More than 86% of the respondents incorrectly answered that antibiotics are effective against colds. The average attitude score on antibiotic use was 6.1 out of 11. A quarter of the interviewees agreed that they gave family members antibiotics wherever they fell sick. Respondents aged 40–49 years and teaching in secondary school had higher odds for adequate knowledge in antibiotic use. Conclusions This study has identified significant knowledge and attitude gaps that need to be addressed by policy makers to ensure rational antibiotics use among teachers and in ensuring effective use of teachers in raising awareness in school communities for rational antibiotic use.Item Insecticide Resistance and Its Intensity in Urban Anopheles Arabiensis in Kisumu City, Western Kenya: Implications for Malaria Control in Urban Areas(PLoS ONE, 2024-11) MachaniI, Maxwell G.; Nzioki, Irene; Onyango, Shirley A.; Onyango, Brenda; Githure, John; Atieli, Harrysone; Wang, Chloe; Lee, Ming-Chieh; Githeko, Andrew K.Background The rise of insecticide resistance poses a growing challenge to the effectiveness of vector control tools, particularly in rural areas. However, the urban setting has received comparatively less focus despite its significance in attracting rural to urban migration. Unplanned urbanization, often overlooked, exacerbates insecticide resistance as Anopheles mosquitoes adapt to the polluted environments of rapidly expanding cities. This study aimed to assess the insecticide susceptibility status of malaria vectors and identify potential underlying mechanisms across three distinct ecological settings characterized by differing levels of urbanization in Kisumu County, Kenya. Methods The study was conducted in 2022–2023 in Kisumu County, western Kenya. Field-derived An. gambiae (s.l.) larvae collected from a long stretch of urban-to-rural continuum were phenotyped as either resistant or susceptible to six different insecticides using the World Health Organization (WHO) susceptibility test. Polymerase chain reaction (PCR) techniques were used to identify the species of the An. gambiae complex and screened for mutations at voltage-gated sodium channels (Vgsc-1014F, Vgsc-1014S, Vgsc-1575Y) and acetylcholinesterase (Ace1) target site mutation 119S. Metabolic enzyme activities (non-specific β-esterases and monooxygenases) were evaluated in mosquitoes not exposed to insecticides using microplate assays. Additionally, during larval sampling, a retrospective questionnaire survey was conducted to determine pesticide usage by the local inhabitants. Results Anopheles arabiensis dominated in urban (96.2%) and peri-urban (96.8%) areas, while An. gambiae (s.s.) was abundant in rural settings (82.7%). Urban mosquito populations showed high resistance intensity to deltamethrin (Mortality rate: 85.2% at 10x) and suspected resistance to Pirimiphos-methyl and bendiocarb while peri-urban and rural populations exhibited moderate resistance intensity to deltamethrin (mortality rate >98% at 10x). Preexposure of mosquitoes to a synergist piperonyl butoxide (PBO) significantly increased mortality rates: from 40.7% to 88.5% in urban, 51.9% to 90.3% in peri-urban, and 55.4% to 87.6% in rural populations for deltamethrin, and from 41.4% to 78.8% in urban, 43.7% to 90.7% in peri-urban, and 35% to 84.2% in rural populations for permethrin. In contrast, 100% mortality to chlorfenapyr and clothianidin was observed in all the populations tested. The prevalence of L1014F mutation was notably higher in urban An. arabiensis (0.22) unlike the peri-urban (0.11) and rural (0.14) populations while the L1014S mutation was more prevalent in rural An. gambiae (0.93). Additionally, urban An. arabiensis exhibited elevated levels of mixed function oxidases (0.8/mg protein) and non-specific esterases (2.12/mg protein) compared to peri-urban (0.57/mg protein and 1.5/mg protein, respectively) and rural populations (0.6/mg protein and 1.8/mg protein, respectively). Pyrethroids, apart from their use in public health through LLINs, were being highly used for agricultural purposes across all ecological settings (urban 38%, peri-urban 36% and rural 37%) followed by amidine group, with organophosphates, neonicotinoids and carbamates being of secondary importance. Conclusion These findings show high resistance of An. arabiensis to insecticides commonly used for vector control, linked with increased levels of detoxification enzymes. The observed intensity of resistance underscores the pressing issue of insecticide resistance in urban areas, potentially compromising the effectiveness of vector control measures, especially pyrethroid-treated LLINs. Given the species’ unique behavior and ecology compared to An. gambiae, tailored vector control strategies are needed to address this concern in urban settings.Item Moringa oleifera has the Potential to Manage HIV-1 and May Enhance the Efficacy of ARVs in Suppressing Viral Loads in HIV/AIDS Patients(IRJPMS, 2024) Wasonga, Wilbroda; Wanyoro, Anthony; Kigondu, Mumbi Elizabeth; Gicheru, Muita MichaelHuman immunodeficiency virus (HIV) infection is managed by expensive ARVs, which also have side effects, and lead to drug resistance and failure. The use of nutritional remedies in managing HIV/AIDS is becoming popular. Moringa oleifera is a nutrient-dense plant with medicinal properties resulting from its wide range of biological activities. This study investigated the beneficial effect of Moringa oleifera supplementation on the viral loads of HIV/AIDS patients receiving antiretroviral drugs (ARVs). A Quasi-Experiment of the regression discontinuity type was conducted at the Comprehensive Care Center, Mbagathi County Hospital, Nairobi, Kenya. We recruited 173 HIV seropositive participants undergoing ARV treatment and attending a regular HIV management clinic. The participants were allocated to the intervention group supplemented with Moringa oleifera leaf powder or the control group, which was not supplemented. The HIV-1 viral load measurements were assessed at the end of the third month and the sixth month of the study period. Analysis was then done to compare the two groups. The study observed that the percentage of participants with non-detectable viral load in the intervention group increased by 7.23%. In comparison, that of the control group decreased by 10.29% by the end of the study period. The study concluded that M. oleifera has the potential to inhibit HIV-1 and may enhance the efficacy of ARVs in suppressing viral loads in HIV/AIDS patients.Item Molecular characterization and genotype distribution of thioester-containing protein 1 gene in Anopheles gambiae mosquitoes in western Kenya(Malaria Journal, 2022) Onyango, Shirley A.; Ochwedo, Kevin O.; Machani, Maxwell G.; Olumeh, Julius O.; Debrah, Isaiah; Omondi, Collince J.; Ogolla, Sidney O.; Ming Chieh, Lee; Guofa, Zhou; Kokwaro, Elizabeth; Kazura, James W.; Afrane, Yaw A.; Githeko, Andrew K.; Zhong, Daibin; Yan, GuiyunBackground: Evolutionary pressures lead to the selection of efcient malaria vectors either resistant or susceptible to Plasmodium parasites. These forces may favour the introduction of species genotypes that adapt to new breeding habitats, potentially having an impact on malaria transmission. Thioester-containing protein 1 (TEP1) of Anopheles gambiae complex plays an important role in innate immune defenses against parasites. This study aims to character ize the distribution pattern of TEP1 polymorphisms among populations of An. gambiae sensu lato (s.l.) in western Kenya. Methods: Anopheles gambiae adult and larvae were collected using pyrethrum spray catches (PSC) and plastic dippers respectively from Homa Bay, Kakamega, Bungoma, and Kisumu counties between 2017 and 2020. Collected adults and larvae reared to the adult stage were morphologically identifed and then identifed to sibling species by PCR. TEP1 alleles were determined in 627 anopheles mosquitoes using restriction fragment length polymorphisms polymerase chain reaction (RFLP-PCR) and to validate the TEP1 genotyping results, a representative sample of the alleles was sequenced. Results: Two TEP1 alleles (TEP1*S1 and TEP1*R2) and three corresponding genotypes (*S1/S1, *R2/S1, and *R2/R2) were identifed. TEP1*S1 and TEP1*R2 with their corresponding genotypes, homozygous *S1/S1 and heterozygous *R2/S1 were widely distributed across all sites with allele frequencies of approximately 80% and 20%, respectively both in Anopheles gambiae and Anopheles arabiensis. There was no signifcant diference detected among the popula tions and between the two mosquito species in TEP1 allele frequency and genotype frequency. The overall low levels in population structure (FST=0.019) across all sites corresponded to an efective migration index (Nm=12.571) and low Nei’s genetic distance values (<0.500) among the subpopulation. The comparative fxation index values revealed minimal genetic diferentiation between species and high levels of gene fow among populations. Conclusion: Genotyping TEP1 has identifed two common TEP1 alleles (TEP1*S1 and TEP1*R2) and three corre sponding genotypes (*S1/S1, *R2/S1, and *R2/R2) in An. gambiae s.l. The TEP1 allele genetic diversity and population structure are low in western Kenya.Item Genetic diversity and population structure of the human malaria parasite Plasmodium falciparum surface protein Pfs47 in isolates from the lowlands in Western Kenya(PLOS ONE, 2021-11-29) Onyango, Shirley A.; Ochwedo, Kevin O.; Machani, Maxwell G.; Omondi, Collince J.; Debrah, Isaiah; Ogolla, Sidney O.; Ming-Chieh, Lee; Guofa, Zhou; Kokwaro, Elizabeth; Kazura, James W.; Afrane, Yaw A.; Githeko, Andrew K.; Daibin, Zhong; Guiyun, YanPlasmodium falciparum parasites have evolved genetic adaptations to overcome immune responses mounted by diverse Anopheles vectors hindering malaria control efforts. Plasmo dium falciparum surface protein Pfs47 is critical in the parasite’s survival by manipulating the vector’s immune system hence a promising target for blocking transmission in the mos quito. This study aimed to examine the genetic diversity, haplotype distribution, and popula tion structure of Pfs47 and its implications on malaria infections in endemic lowlands in Western Kenya. Cross-sectional mass blood screening was conducted in malaria endemic regions in the lowlands of Western Kenya: Homa Bay, Kombewa, and Chulaimbo. Dried blood spots and slide smears were simultaneously collected in 2018 and 2019. DNA was extracted using Chelex method from microscopic Plasmodium falciparum positive samples and used to genotype Pfs47 using polymerase chain reaction (PCR) and DNA sequencing. Thirteen observed haplotypes of the Pfs47 gene were circulating in Western Kenya. Popula tion-wise, haplotype diversity ranged from 0.69 to 0.77 and the nucleotide diversity 0.10 to 0.12 across all sites. All the study sites displayed negative Tajima’s D values although not significant. However, the negative and significant Fu’s Fs statistical values were observed across all the study sites, suggesting population expansion or positive selection. Overall genetic differentiation index was not significant (FST = -0.00891, P > 0.05) among parasite populations. All Nm values revealed a considerable gene flow in these populations. These results could have important implications for the persistence of high levels of malaria trans mission and should be considered when designing potential targeted control interventions.Item The Potential for Use of Haematological and Anti-Ige Humoral Responses as Phenotypic Markers for Tick Resistance in Cattle(Elsevier B.V, 2023-11-23) Ngetich, Collins; Kamau, Lucy; Simbauni, Jemimah; Mwendia, Charles; Owido, Milton; Kiio, Irene; Matika, Oswald; Foster, Sarah; Birkett, Michael; Djikeng, Appolinaire; Watson, Kellie Anne; Githaka, NaftalyApproximately 80% of the global cattle population is at risk of infestation and infection by ticks and tick-borne diseases (TTBDs). The economic losses from animal mortality, reduced production, vector control costs and animal treatment are very substantial, hence there is an urgent need to develop and deploy alternative vector control strategies. Breeding for host tick resistance has the potential for sustainable large-scale TTBD control especially in cattle. The gold standard method for phenotyping tick resistance in cattle is by counting ticks on the body but is very laborious and subjective. Better methods for phenotyping tick resistance more objectively, faster and at scale, are essential for selecting host genetic resistance to ticks. This study investigated the correlation between haematological cellular profiles and immunological responses (immunoglobulin E, IgE) and full body tick counts in herds of Bos indicus and Bos taurus following artificial tick challenge with Rhipicephalus decoloratus larvae. Fifty-four Friesian and Ayrshire (Bos taurus) and 52 East African Zebu (Bos indicus) calves were each infested with ~2500 larvae. Near-replete adult female ticks (≥ 4.5 mm) were counted daily from Day 20–25. Blood and serum samples were obtained from each animal on Days 0 and 23 for cellular blood and IgE titre analysis, respectively. The indicine cattle were refractory to R. decoloratus infestation in comparison with the taurine breed (P < 0.0001). Repeated measurements of blood components pre-infestation revealed a significant (P < 0.05) association with tick count in IgE and red blood cells, haematocrit, and haemoglobin post-infestation. There was also a strong positive correlation between the tick counts and red blood cell numbers, haemoglobin, haematocrit, and IgE concentration (P < 0.0001) following tick challenge. The application of this approach to phenotype host resistance needs to be assessed using higher cattle numbers and with different tick species or generaItem Community-Managed Coral Reef Restoration in Southern Kenya Initiates Reef Recovery Using Various Artificial Reef Designs(Frontiers in Marine Science, 2023-04) Knoester, EG.; Rienstra, JJ.; Schürmann, QJF.; Wolma, AE.; Murk, AJ.; Osinga, R.Monitoring of reef restoration efforts and artificial reefs (ARs) has typically been limited to coral fragment survival, hampering evaluation of broader objectives such as ecosystem recovery. This study aimed to determine to what extent AR design influences the ecological recovery of restored reefs by monitoring outplanted coral fragments, benthic cover, coral recruitment and fish and invertebrate communities for two years. Four AR designs (16 m2 ), unrestored controls and natural reef patches as reference (n = 10) were established in Mkwiro, Kenya. ARs consisted either of concrete disks with bottles, layered concrete disks, metal cages or a combination thereof. A mixture of 18 branching coral species (mainly Acropora spp.) was outplanted on ARs at a density of 7 corals m-2. After two years, 60% of all outplanted fragments had survived, already resulting in coral cover on most ARs comparable (though Acropora-dominated) to reference patches. Coral survival differed between ARs, with highest survival on cages due to the absence of crown-of-thorns sea star predation on this design. In total, 32 coral genera recruited on ARs and recruit densities were highest on reference patches, moderate on concrete ARs and low on cages. ARs and reference patches featured nearly twice the fish species richness and around an order of magnitude higher fish abundance and biomass compared to control patches. Fish abundance and biomass strongly correlated with coral cover on ARs. AR, reference and control patches all had distinct fish species compositions, but AR and reference patches were similar in terms of trophic structure of their fish communities. Motile invertebrates including gastropods, sea urchins, sea cucumbers and sea stars were present at ARs, but generally more abundant and diverse at natural reference patches. Taken together, all studied ecological parameters progressed towards reef ecosystem recovery, with varying influences of AR design and material. We recommend a combination of metal cages and layered concrete ARs to promote high fragment survival as well as natural coral recruitment. Ultimately, a longer period of monitoring is needed to fully determine the effectiveness reef restoration as conservation tool to support coral reef ecosystem recoveryItem DNA Barcoding, Dwelling Morphology, and Fecundity of the Gall-Forming Shrimp Paratypton Siebenrocki Balss, 1914 (Caridea: Palaemonidae)(Tylor and Francis, 2023) van der Meij, Sancia E. T.; Bouwmeester, Jessica; Bähr, SusanneTropical coral reefs offer a wide variety of habitats to countless invertebrate species. Sessile host organisms especially are inhabited by small taxa, of which decapod crustaceans form one of the most diverse communities. Symbiotic palaemonid shrimp species associate with marine invertebrate hosts from multiple phyla, including cnidarians such as stony corals (Scleractinia). The intriguing gallforming shrimp Paratypton siebenrocki, a symbiont of Acropora corals in the Indo-Pacific, was collected in the Saudi Arabian Red Sea, Kenya, and the Maldives. Based on morphology P. siebenrocki has been considered to be most closely related to the genera Anapontonia and Metapontonia; however, no clear clustering with either palaemonid genus was observed in a phylogenetic reconstruction based on 16S and COI mtDNA. Here we photo-document the dwellings of P. siebenrocki in Acropora spp. for the first time, and furthermore we report on the reproductive output of this species. The number of eggs ranged from 345 to 909 (n = 6), and embryo volume differed strongly between early- and late-stage embryos. The carapace length ranged from 2.58 to 4.55 mm for the females and 1.51 to 2.5 mm for the males (n = 5). The number and size of the embryos, combined with their specialised, secluded lifestyle, suggest that P. siebenrocki allocates higher energy towards embryo production than free-living confamilials do.Item Terminalia brownii Fresen: Stem Bark Dichloromethane Extract Alleviates Pyrogallol-Induced Suppression of Innate Immune Responses in Swiss Albino Mice(Hindawi, 2023-02) Mbiri, Jane Wanja; Ogila, Kenneth; Kisangau, Patrick; Gicheru, MichaelKala-azar is a parasitic disease caused by Leishmania species transmitted by sand fly. In Kenya, kala-azar is endemic in thirty subcounties spread over in eleven counties in the arid zones. Climate change-influenced seasonal weather variability and environmental alterations remain important determinants of many vector-borne diseases. The present study focused on climate change and environmental influence on kala-azar in West Pokot. A descriptive cross-sectional and retrospective research design was adapted. Study area was purposively selected. Locations were randomly selected, and households were systematically selected. Three hundred sixty-three household questionnaires, eleven key informant interviews, and five focus group discussions were undertaken. Secondary data were obtained from Kacheliba subcounty hospital records. Statistical Package for the Social Sciences version 24 was used to analyze quantitative data while qualitative data were analyzed to establish connection for interpretation. Kala-azar cases have been on the rise on aggregate and surge towards the end of dry season and just after the rains. Significant environmental factors included the presence of seasonal rain water pathways and rock piles around houses (AOR = 4.7; 95% CI = (2.3-9.6), ), presence of acacia trees in and around homesteads (AOR = 8.5; 95% CI = (2.5-28.6), ), presence of anthills around the homesteads (AOR = 5.2; 95% CI = (1.2-23.4), ), and presence of animal shed within compound (AOR = 2.8; 95% CI = (0.96-8), ). Climate change-induced seasonal weather variability, increased temperature and reduced precipitation as well as environmental alterations influence kala-azar occurrence in West Pokot. Community sensitization on disease prevalence, clearing of vector predilection sites, and improving community environmental risk perception are imperative to promote prevention.Item Evaluation of the Therapeutic Potential of Warburgia ugandensis, Prunus africana, and Piliostigma thonningii against Leishmania donovani in vitro and in Balb/c Mice(Bilingual Publishing, 2022-10) Mogaka, Maria Divinah; Mutiso, Joshua M.; Macharia, John C.; Ayako, Rebecca M.; Osero, Bernard; Gicheru, Michael M.Leishmaniasis is a zoonotic disease caused by protozoan parasites of the genus Leishmania. Conventional chemotherapy remains to be the most preferred measure against leishmaniasis despite being associated with high toxicity and relapse rates. They are also expensive and require hospitalization. Plant-based compounds provide a better treatment alternative because they are effective, cheap, and less associated with toxicity and resistance. This study examined the therapeutic potential of Warburgia ugandensis, Prunus africana, and Piliostigma thonningii against Leishmania donovani infection in BALB/c mice. Anti-promastigote and toxicity studies were evaluated by incubating the test compound with promastigotes and Vero cells, respectively. Serum was obtained from the mice for total immunoglobulin gamma (IgG) quantification. For in vivo studies, the mice were infected with virulent Leishmania donovani then treated with methanolic extracts of Warburgia ugandensis, Prunus africana, and Piliostigma thonningii and control drug, pentostam (sodium stibogluconate). Treatment with the plant extracts and standard drug resulted to significant reduction in parasite burden. Outcomes in the mice treated with plant extracts were comparable to those treated with pentostam (P≥0.05). In the promastigote assay, all the test compounds killed more than half of the promastigotes at the highest concentration (500 µg/mL). Warburgia ugandensis, P. thonningii, and P. africana reduced the number of promastigotes from 2.0 × 106 to 7.7 × 103 , 72.0 × 103 , and 5.0 × 103 , respectively. Pentostam had the lowest IC50 (210 µg/mL), followed by Warburgia ugandensis (IC50 of 270 µg/mL). Piliostigma thonningii and P. africana were less toxic with IC50 of 720 µg/mL and 500 µg/mL, respectively. There was low production of IgG antibodies following treatment with the plant extracts and high levels in the untreated control.Item Alarming Cases of Cancer in Kenya: A Case for Meru and Tharaka Nithi Counties(Society for Science and Education, 2023-01) Mutiso, Joshua; Gitonga, Ciriaka; Abdullahi, Bulle; Simbauni, Jemimah; Gicheru, MichaelBackground: Cancer is one of the leading causes of morbidity and mortality worldwide. In Kenya, cancer as a disease ranks third as a cause of death after infectious and cardiovascular diseases and the cancer cases are increasing at an alarming rate. Objective: The current study was aimed at determining the prevalence trends of cancer in Meru and Tharaka Nithi Counties with an aim of putting proper infrastructural and human capacity development to combat cancer. Methods: A random selection of patients aged between five to eighty-two years clinically diagnosed as cancer patients who were visiting Meru and Chuka General Hospitals for a period of one year were recruited for the study. The participants were requested to give a verbal consent and respond to a brief questionnaire concerning their gender, age and the type of cancer they are suffering from. This study used retrogressive approach where the trend of cancer incidences and death rate were determined for the last eight years (2011 to 2018) using the hospital data. Data were analysed using statistical package for social sciences (SPSS). Results: This study established that the prevalence of cancer in people visiting hospitals in Meru and Tharaka Nithi Counties was 0.32% and 0.38% respectively. Further, the prevalence trends of cancer cases in the two counties have been increasing over the last eight years. Conclusion: The study concludes that cancer is prevalent in Meru and Tharaka Nithi Counties. It is therefore recommended that proper infrastructural and human capacity development be put in place to combat cancer.Item Differences in Malaria Vector Biting Behavior and Changing Vulnerability to Malaria Transmission in Contrasting Ecosystems of Western Kenya(Parasites & Vectors, 2023-10) Nzioki, Irene; Machani, Maxwell G.; Onyango, Shirley A.; Kabui, Kevin K.; Githeko, Andrew K.; Ochomo, Eric; Yan, Guiyun; Afrane, Yaw A.Background Designing, implementing, and upscaling of efective malaria vector control strategies necessitates an understanding of when and where transmission occurs. This study assessed the biting patterns of potentially infectious malaria vectors at various hours, locations, and associated human behaviors in diferent ecological settings in western Kenya. Methods Hourly indoor and outdoor catches of human-biting mosquitoes were sampled from 19:00 to 07:00 for four consecutive nights in four houses per village. The human behavior study was conducted via questionnaire surveys and observations. Species within the Anopheles gambiae complex and Anopheles funestus group were distinguished by polymerase chain reaction (PCR) and the presence of Plasmodium falciparum circumsporozoite proteins (CSP) determined by enzyme-linked immunosorbent assay (ELISA). Results Altogether, 2037 adult female anophelines were collected comprising the An. funestus group (76.7%), An. gambiae sensu lato (22.8%), and Anopheles coustani (0.5%). PCR results revealed that Anopheles arabiensis constituted 80.5% and 79% of the An. gambiae s.l. samples analyzed from the lowland sites (Ahero and Kisian, respectively). Anopheles gambiae sensu stricto (hereafter An. gambiae) (98.1%) was the dominant species in the highland site (Kimaeti). All the An. funestus s.l. analyzed belonged to An. funestus s.s. (hereafter An. funestus). Indoor biting densities of An. gambiae s.l. and An. funestus exceeded the outdoor biting densities in all sites. The peak biting occurred in early morning between 04:30 and 06:30 in the lowlands for An. funestus both indoors and outdoors. In the highlands, the peak biting of An. gambiae occurred between 01:00 and 02:00 indoors. Over 50% of the study population stayed outdoors from 18:00 to 22:00 and woke up at 05:00, coinciding with the times when the highest numbers of vectors were collected. The sporozoite rate was higher in vectors collected outdoors, with An. funestus being the main malaria vector in the lowlands and An. gambiae in the highlands. Conclusion This study shows heterogeneity of anopheline distribution, high outdoor malaria transmission, and early morning peak biting activity of An. funestus when humans are not protected by bednets in the lowland sites. Additional vector control eforts targeting the behaviors of these vectors, such as the use of non-pyrethroids for indoor residual spraying and spatial repellents outdoors, are needed.Item Utilization of Reproductive Health Services and Associated Factors among Youths in Mombasa County, Kenya(IJTDH, 2023-08) Yonge, Shadrack A.; Opiyo, Bob; Kibira, Agnes W.; Sharma, Rekha R.Background: Reproductive health has become a global concern that is either poorly understood or not fully appreciated among the youth. Access to reproductive health services is important for protecting youth from STIs and unwanted pregnancy problems. Aim: The study sought to establish utilization of reproductive healthcare services and associated factors among youths in Mombasa County, Kenya. Study Design: A descriptive cross-sectional study was carried out between August 2018 and January 2019. Methodology: A self-administered, structured questionnaire was utilized to gather information. The information gathered was summarized using an SPSS database. The data was analyzed with SPSS version 22. Logistic regression was done to identify possible factors associated with reproductive health service utilization. p-value less than 0.05 was considered as a level of significance. Results: A total of 384 youth participated in the study, including 200 (62.2% females and 184 (37.8%) males. The media was the main source of information for modern family planning methods 200 (50. 1%). The majority of users 326 (84.9%) sought contraceptives from pharmacies. 213 (55.5%) were utilizing modern contraceptives. HIV/AIDS risk perception was significantly associated with utilization of reproductive health services [COR=2.34, 95% CI: 2.19-5.34].The condom was the most used method 134 (34.9%). Having knowledge about reproductive health services [COR=2.87; 95% CI: 1.92-3.94] was positively associated with the outcome. Male respondents were three (3) times more likely to use condoms [OR = 2.86, 95% Cl: 1.82-4.91] than female respondents. Conclusion: There was low uptake of contraceptive services among the youth who were sexually active. The condom was the most commonly used contraceptive. Strengthening urban healthcare systems is key to have equality and improve accessibility of FP services among the teenagers and young women.Item Where to Fish in the Forest? Tree Characteristics and Contiguous Seagrass Features Predict Mangrove Forest Quality for Fishes and Crustaceans(Journal of Applied Ecology, 2023) Wanjiru, Caroline; Nagelkerken, Ivan; Rueckert, Sonja; Harcourt, William; Huxham, Mark1. Mangroves often support rich fish and crustacean communities, although faunal abundance and diversity show strong spatiotemporal variability. Consistent patterns in mangrove animal communities might be dictated by forest characteristics, by seascape context or by some combination of these factors. Predicting drivers of spatial heterogeneity in mangrove faunal communities can better support the zoning of forests for management purposes, for example by identifying sites important for fisheries nursery provision. 2. We sampled 14 sites within a large (4000 ha) mangrove forest in Kenya, quarterly over a period of 2 years. There were clear and consistent differences in the quality of sites for fish and crustacean abundance and diversity. 3. Forest characteristics (as summarised by the complexity index, CI) and seascape metrics (the presence, area and configuration of contiguous seagrass) were strong predictors of site differences. However, they showed opposite influences on dominant members of the fish and crustacean faunas, with CI correlated negatively with fishes and positively with crustaceans, and seagrass area correlated positively with fishes and negatively with crustaceans. 4. Synthesis and applications. Sites within the same mangrove forest exhibit consistent differences in fish and crustacean abundance. However, the fish and crustacean communities (and particularly dominant species within them) act differently in response to forest and seascape characteristics. Old growth, mature forest, set in a seascape of seagrass patches with bare sediment, was associated with highest crustacean abundance. In contrast, denser smaller trees and seascapes with larger, continuous areas of seagrass correlated better with fish abundance. Zoning for management, as mandated in new Kenyan policy, will need to consider these differences in seascape use between fish and crustaceans.Item Forecasting the Potential Effects of Climate Change on Malaria in the Lake Victoria Basin Using Regionalized Climate Projections(Springer Nature, 2022-08-12) Ototo, Ednah N.; Ogutu, Joseph O.; Githeko, Andrew; Said, Mohammed Y.; Kamau, Lucy; Namanya, Didacus; Simiyu, Stella; Mutimba, StephenBackground Malaria epidemics are increasing in East Africa since the 1980s, coincident with rising temperature and widening climate variability. A projected 1–3.5 °C rise in average global temperatures by 2100 could exacerbate the epidemics by modifying disease transmission thresholds. Future malaria scenarios for the Lake Victoria Basin (LVB) are quantified for projected climate scenarios spanning 2006–2100. Methods Regression relationships are established between historical (1995–2010) clinical malaria and anaemia cases and rainfall and temperature for four East African malaria hotspots. The vector autoregressive moving average processes model, VARMAX (p,q,s), is then used to forecast malaria and anaemia responses to rainfall and temperatures projected with an ensemble of eight General Circulation Models (GCMs) for climate change scenarios defined by three Representative Concentration Pathways (RCPs 2.6, 4.5 and 8.5). Results Maximum temperatures in the long rainy (March–May) and dry (June–September) seasons will likely increase by over 2.0 °C by 2070, relative to 1971–2000, under RCPs 4.5 and 8.5. Minimum temperatures (June–September) will likely increase by over 1.5–3.0 °C under RCPs 2.6, 4.5 and 8.5. The short rains (OND) will likely increase more than the long rains (MAM) by the 2050s and 2070s under RCPs 4.5 and 8.5. Historical malaria cases are positively and linearly related to the 3–6-month running means of monthly rainfall and maximum temperature. Marked variation characterizes the patterns projected for each of the three scenarios across the eight General Circulation Models, reaffirming the importance of using an ensemble of models for projections. Conclusions The short rains (OND), wet season (MAM) temperatures and clinical malaria cases will likely increase in the Lake Victoria Basin. Climate change adaptation and mitigation strategies, including malaria control interventions could reduce the projected epidemics and cases. Interventions should reduce emerging risks, human vulnerability and environmental suitability for malaria transmission