Medical Microbiology

The Use of Photomicrographs and Real Specimens in Teaching Biology in Secondary Schools and its Effects on Students Performance, Kenya

Mon, 01 Jan 2024 00:00:00 GMT

The Use of Photomicrographs and Real Specimens in Teaching Biology in Secondary Schools and its Effects on Students Performance, Kenya Jerono, Caroline; Samikwo, Dinah; Ouma, Peter The study focused on examining the effect of teaching secondary school biology using photomicrographs and real specimens to enhance students’ academic performance in secondary schools in Kenya.it employed the constructivism theory which emphasizes that in a constructivist environment, learners are able to build their own understanding by use of their previous knowledge to create new ideas. A teacher in a realism classroom is just but a facilitator who guides the active learners towards making their own conclusion. Students’ previous knowledge is prompted to ascertain what they know before a concept is taught. That would enable the teacher to correct any misconception that would arise and therefore concepts would be built on factual knowledge leading to learning of new concepts. The target population was 1490, where 298 form one Biology student and 18 teachers were used as the respondents. The Quasi –experimental design was used in the study where a pre-test Standardized Biology evaluation test (SBET) was administered to all the study participants. Then a treatment offered and later a post-test Standardized Biology evaluation test (SBET) to both groups corresponding to treatment given. The target population was 1490, where 298 form one Biology student and 18 teachers were used as the respondents. The population of interest were identified using stratified sampling and simple random sampling techniques. The Standardized Biology Evaluation Test SBET, a questionnaire for teachers TQ and for students SQ and checklist instruments were used as data collection instruments to generate data. For establishment of consistency of the questionnaire, Cronbach’s Alpha coefficient that estimates the reliability of the instrument was used which gave Cronbach’s coefficient alpha of 0.89 for students and 0.84 for teachers. The data analysis were carried out using descriptive statistics and inferential statistics (t-test) guided by SPSS and excel. The study found out that the students in the experimental group outperformed those in the control group. The study recommended that the Teachers Service Commission (TSC) should provide the use of real specimens teaching approach in secondary schools in order to improve performance in KCSE Biology Examinations. http://41.89.164.27:8080/xmlui/handle/123456789/2369

The impact of sulfadoxine–pyrimethamine resistance on the effectiveness of intermittent preventive treatment for the prevention of malaria in pregnancy in Africa: an updated systematic review and meta-analysis

Mon, 14 Jul 2025 00:00:00 GMT

The impact of sulfadoxine–pyrimethamine resistance on the effectiveness of intermittent preventive treatment for the prevention of malaria in pregnancy in Africa: an updated systematic review and meta-analysis van Eijk, Anna Maria; Stepniewska, Kasia; Khairallah, Carole.et al. Resistance of Plasmodium falciparum to sulfadoxine–pyrimethamine threatens the antimalarial effectiveness of intermittent preventive treatment during pregnancy (IPTp) with sulfadoxine–pyrimethamine (ITPp-SP) in sub-Saharan Africa. We updated an aggregated-data meta-analysis to assess the associations between sulfadoxine–pyrimethamine resistance and the effectiveness of IPTp-SP to inform policy. journal of The Lancet Infectious Diseases

Patient preferences for HIV service delivery models; a Discrete Choice Experiment in Kisumu, Kenya. PLOS Glob Public Health 2 (10): e0000614

Thu, 27 Oct 2022 00:00:00 GMT

Patient preferences for HIV service delivery models; a Discrete Choice Experiment in Kisumu, Kenya. PLOS Glob Public Health 2 (10): e0000614 Mando, R.O; Moghadassi, M; Juma, E; Ogollah, C; Packel, L; Kulzer, J.L Novel “differentiated service delivery” models for HIV treatment that reduce clinic visit frequency, minimize waiting time, and deliver treatment in the community promise retention improvement for HIV treatment in Sub-Saharan Africa. Quantitative assessments of differentiated service delivery (DSD) feature most preferred by patient populations do not widely exist but could inform selection and prioritization of different DSD models. We used a discrete choice experiment (DCE) to elicit patient preferences of HIV treatment services and how they differ across DSD models. We surveyed 18+year-olds, enrolled in HIV care for �6 months between February-March, 2019 at four facilities in Kisumu County, Kenya. DCE offered patients a series of comparisons between three treatment models, each varying across seven attributes: ART refill location, quantity of dispensed ART at each refill, medication pick-up hours, type of adherence support, clinical visit frequency, staff attitude, and professional cadre of person providing ART refills. We used hierarchical Bayesian model to estimate attribute importance and relative desirability of care characteristics, latent class analysis (LCA) for groups of preferences and mixed logit model for willingness to trade analysis. Of 242 patients, 128 (53.8%) were females and 150 (62.8%) lived in rural areas. Patients placed greatest importance on ART refill location [19.5% (95% CI 18.4, 10.6) and adherence support [19.5% (95% CI 18.17, 20.3)], followed by staff attitude [16.1% (95% CI 15.1, 17.2)]. In the mixed logit, patients preferred nice attitude of staff (coefficient = 1.60), refill ART health center (Coeff = 1.58) and individual adherence support (Coeff = 1.54), 3 or 6 months for ART refill (Coeff = 0.95 and 0.80, respectively) and pharmacists (instead of lay health workers) providing ART refill (Coeff = 0.64). No differences were observed by gender or urbanicity. LCA revealed two distinct groups (59.5% vs. 40.5%). Participants preferred 3 to 6-month refill interval or clinic visit spacing, which DSD offers stable patients. While DSD has encouraged community ART group options, our results suggest strong preferences forART refills from health-centers or pharmacists over lay-caregivers or community members. These preferences held across gender&urban/rural subpopulations.

Campylobacter in Africa – A specific viewpoint

Thu, 21 Dec 2023 00:00:00 GMT

Campylobacter in Africa – A specific viewpoint Ellis Kobina Paintsil, Wycliffe O Masanta, Annika Dreyer, Leonid Ushanov, Stella I Smith, Hagen Frickmann, Andreas E Zautner Campylobacter infections and campylobacteriosis-associated post-infectious sequelae are a significant global health burden that needs to be addressed from a specific African perspective. We conducted a comprehensive literature search on NCBI PubMed to compile a comprehensive narrative review article on Campylobacter infections in Africa, focusing on key aspects in human and veterinary medicine as well as food hygiene. We specifically focused on the epidemiology of enteropathogenic Campylobacter spp. in sub-Saharan and North Africa considering antimicrobial susceptibility. The most significant sequela resulting from molecular mimicry to Campylobacter surface structures is the Guillain-Barré syndrome, which was mainly examined in the context of limited studies conducted in African populations. A dedicated subsection is allocated to the limited research on the veterinary medically important species Campylobacter fetus. There are significant differences in the composition of the gut microbiome, especially in rural areas, which affect the colonization with Campylobacter spp. and the manifestation of campylobacteriosis. There may be a problem of overdiagnosis due to asymptomatic colonization, particularly in the detection of Campylobacter using molecular biological techniques. To reduce the colonization and infection rate of Campylobacter, we propose implementing several control measures and urge further research to improve the current understanding of the peculiarities of campylobacteriosis in Africa. DOI: https://doi.org/10.1556/1886.2023.00043

Diversity and taxonomic revision of methanogens and other archaea in the intestinal tract of terrestrial arthropods

Sat, 11 Nov 2023 00:00:00 GMT

Diversity and taxonomic revision of methanogens and other archaea in the intestinal tract of terrestrial arthropods Evgenii Protasov, James O Nonoh, Joana M Kästle Silva, Undine S Mies, Vincent Hervé, Carsten Dietrich, Anja Poehlein, Hamadi I Boga, David K Ngugi, Jan Šobotník, Rolf Daniel, Andreas Brune Methane emission by terrestrial invertebrates is restricted to millipedes, termites, cockroaches, and scarab beetles. The arthropod-associated archaea known to date belong to the orders Methanobacteriales, Methanomassiliicoccales, Methanomicrobiales, and Methanosarcinales, and in a few cases also to non-methanogenic Nitrososphaerales and Bathyarchaeales. However, all major host groups are severely undersampled, and the taxonomy of existing lineages is not well developed. Full-length 16S rRNA gene sequences and genomes of arthropod-associated archaea are scarce, reference databases lack resolution, and the names of many taxa are either not validly published or under-classified and require revision. Here, we investigated the diversity of archaea in a wide range of methane-emitting arthropods, combining phylogenomic analysis of isolates and metagenome-assembled genomes (MAGs) with amplicon sequencing of full-length 16S rRNA genes. Our results allowed us to describe numerous new species in hitherto undescribed taxa among the orders Methanobacteriales (Methanacia, Methanarmilla, Methanobaculum, Methanobinarius, Methanocatella, Methanoflexus, Methanorudis, and Methanovirga, all gen. nova), Methanomicrobiales (Methanofilum and Methanorbis, both gen. nova), Methanosarcinales (Methanofrustulum and Methanolapillus, both gen. nova), Methanomassiliicoccales (Methanomethylophilaceae fam. nov., Methanarcanum, Methanogranum, Methanomethylophilus, Methanomicula, Methanoplasma, Methanoprimaticola, all gen. nova), and the new family Bathycorpusculaceae (Bathycorpusculum gen. nov.). Reclassification of amplicon libraries from this and previous studies using this new taxonomic framework revealed that arthropods harbor only CO2 and methyl-reducing hydrogenotrophic methanogens. Numerous genus-level lineages appear to be present exclusively in arthropods, suggesting long evolutionary trajectories with their termite, cockroach, and millipede hosts, and a radiation into various microhabitats and ecological niches provided by their digestive tracts (e.g., hindgut compartments, gut wall, or anaerobic protists). The distribution patterns among the different host groups are often complex, indicating a mixed mode of transmission and a parallel evolution of invertebrate and vertebrate-associated lineages.

Characterization of Anopheles funestus Larval Habitats in Fiyoni, Kwale County, Kenya: Insights into Malaria Vector Ecology and Control

Wed, 25 Oct 2023 00:00:00 GMT

Characterization of Anopheles funestus Larval Habitats in Fiyoni, Kwale County, Kenya: Insights into Malaria Vector Ecology and Control Omondi, Clifton; Nonoh, James; Ntabo, Regina The breeding of malaria-spreading vectors such as Anopheles funestus is influenced by various environmental factors that contribute indirectly to the transmission of the Plasmodium parasite. However, there is limited knowledge of larval habitat ecology that hinder prevention and control of mosquito-borne diseases. This study aimed to characterize larval habitats based on physicochemical and habitat characteristics, considering the abundance of A. funestus. A cross-sectional survey method was used to collect data on the established transects. Physical parameters (water temperature, pH, conductivity, and total dissolved solids) were measured using a 5-in-1 meter probe. Levels of chemical parameters (sulphate, COD, and BOD) were determined in the laboratory using standard methods. Observations were also made on habitat characteristics (including watercolor, habitat size, and canopy). There was significant effect (P<0.05) of conductivity, pH, sulphate, COD, and BOD on the number of A. funestus larvae. Water samples with a high population of A. funestus larvae were found to have higher conductivity (Me of 470.5), TDS (Me = 235), and pH levels (Me of 6.71). Conversely, water samples with a high population of non-Anopheles funestus larvae were found to have higher COD (Me of 843.20), BOD (Me of 367.2), and SO4 levels (Me of 11.3). A significant correlation (p<0.5) existed between A. funestus larvae and physical water parameters. For instance, Anopheles funestus larvae was high (Me of 36.85) in stagnant water and in semi-permanent water (Me of 47.37). The study demonstrates that both physicochemical and habitat parameters significantly influence the abundance of Anopheles funestus larvae in larval habitats. Parameters such as conductivity, pH, total dissolved solids, sulphate, COD, BOD, watercolor, depth, distance from the homestead, and habitat size were found to be important in determining the presence of A. funestus larvae. Therefore, vector control strategies should include larval source management by targeting rivers and other water bodies to prevent the emergence of Anopheles funestus.

Antimicrobial Activities of Some Constituents Isolated from a Kenyan Medicinal Plant, Capparis fascicularis DC

Tue, 31 Oct 2023 00:00:00 GMT

Antimicrobial Activities of Some Constituents Isolated from a Kenyan Medicinal Plant, Capparis fascicularis DC Kagika, Mary W; Chhabra, Sumesh C; Nonoh, James OM; Hassanali, Ahmed Capparis fascicularis DC. is an indigenous medicinal plant belonging to the family Capparaceae found in Nyandarua County, Nairobi, Kenya, and many parts of Africa. It is a shrub whose roots are used traditionally to treat colds. Aim. The aim of the present study is to carry out antimicrobial activities of solvent extracts of different parts of Capparis fascicularis, characterize the phytochemical constituents of the most active extract, and identify the most active compounds. Place and Duration of the Study. All the experiments were carried out in the departments of Chemistry and Microbiology, Kenyatta University, Nairobi, Kenya. Methodology. Petroleum ether, ethyl acetate, methanol, and water extracts from the leaves, stem bark, and root bark of C. fascicularis were screened against selected strains of both Gram-positive (Staphylococcus aureus and Bacillus subtilis) and Gram-negative (Salmonella typhimurium and Escherichia coli) bacteria using disc diffusion and tube dilution methods. Fractionation of the most active crude extract was carried out by column chromatography, and the fractions together with the most active crude extract were screened against the selected bacterial strains. The most active fraction was further fractionated, and the subfractions were screened against the bacterial strains to test for possible synergistic effects between the subfractions and their constituents. The most active fraction was then analysed by GC-MS and LC-ESI-MS methods to identify the major constituents. Results. The ethyl acetate extract of C. fascicularis root bark (CFR2) showed a significant in vitro antibacterial activity. From the seven fractions of CFR2 obtained, fraction 2 (F2) had the lowest MIC value and was thus most active. Moreover, F2 was found to be more active compared to the four subfractions obtained from it. This suggested that constituents of F2 worked in synergy. Fraction 2 contained phenols, terpenes, and flavonoids. Two compounds were identified by GC-MS as 2,4-di-tert-butylphenol and (E,E)-2,4-decadienal, while three compounds were identified by LC-ESI-MS as tanshinone II A, cryptotanshinone, and danshensu. Conclusion. The study revealed that CFR2 is the most active extract on bacteria, suggesting that most antimicrobial compounds are concentrated in the roots of C. fascicularis. A follow-up study is directed towards chromatographic separations to obtain the other chemical constituents and screen them against various strains of bacteria. https://doi.org/10.1155/2023/6114501

Profiles of bacterial communities and environmental factors associated with proliferation of malaria vector mosquitoes within the Kenyan Coast

Tue, 01 Aug 2023 00:00:00 GMT

Profiles of bacterial communities and environmental factors associated with proliferation of malaria vector mosquitoes within the Kenyan Coast Josphat Mutinda, Samuel Mwakisha Mwamburi, Kennedy Omondi Oduor, Maurice Vincent Omolo, Regina Mongina Ntabo, James Muhunyu Gathiru, Joseph Mwangangi, James OM Nonoh Since Anopheles mosquitoes which transmit and maintain the malaria parasite breed in the outdoor environment, there is an urgent need to manage these mosquito breeding sites. In order to elaborate more on the ecological landscape of mosquito breeding sites, the bacterial community structure and their interactions with physicochemical factors in mosquito larval habitats was characterised in Kwale County (Kenya), where malaria is endemic. DOI 10.1099/acmi.0.000606.v4

Proteome profiling of Campylobacter jejuni 81-176 at 37° C and 42° C by label-free mass spectrometry

Fri, 05 May 2023 00:00:00 GMT

Proteome profiling of Campylobacter jejuni 81-176 at 37° C and 42° C by label-free mass spectrometry Annika Dreyer, Wycliffe O Masanta, Raimond Lugert, Wolfgang Bohne, Uwe Groß, Andreas Leha, Mohammed Dakna, Christof Lenz, Andreas E Zautner https://doi.org/10.21203/rs.3.rs-2877597/v1

Metagenomic Profiles of Bacterial communities and environmental factors associated with proliferation of malaria vector mosquitoes within the Kenyan Coast

Wed, 12 Apr 2023 00:00:00 GMT

Metagenomic Profiles of Bacterial communities and environmental factors associated with proliferation of malaria vector mosquitoes within the Kenyan Coast Mutinda, Josphat; Mwamburi, Samuel Mwakisha; Oduor, Kennedy Omondi; Omolo, O Maurice; Ntabo, Regina Mongina; Gathiru, James Muhunyu; Mwangangi, Joseph; Nonoh, James Anopheles mosquitoes are the main malaria vector and as malaria cases decline in Sub Saharan Africa, there is a growing realisation that new interventions need to be added to complement the existing control strategies. To date, vector control is the most effective way to prevent malaria. Since the malaria parasite is maintained by mosquitoes which oviposit, feed and rest in the outdoor environment, there is an urgent need to focus on the control of oviposition sites seeking malaria vectors. In this regard, a detailed understanding of their larval ecology is necessary. In this study, the bacterial community structure and their interactions with physicochemical factors in relation to oviposition site selection in mosquito larval habitats was characterised in Kwale County, where malaria is endemic https://doi.org/10.1099/acmi.0.000606.v1