No abstract

The population’s antibody response is a key factor in comprehending SARS-CoV-2 epidemiology. This is especially important in African settings where COVID-19 impact, and vaccination rates are relatively low. This study aimed at characterizing the Immunoglobulin G (IgG) and Immunoglobulin M (IgM) in both SARS-CoV-2 asymptomatic and symptomatic individuals in Kisumu and Siaya counties in western Kenya using enzyme linked immunosorbent assays. The IgG and IgM overall seroprevalence in 98 symptomatic and asymptomatic individuals in western Kenya between December 2021-March 2022 was 76.5% (95% CI = 66.9–84.5) and 29.6% (95% CI = 20.8–39.7) respectively. In terms of gender, males had slightly higher IgG positivity 87.5% (35/40) than females 68.9% (40/58). Amidst the ongoing vaccination roll-out during the study period, over half of the study participants (55.1%, 95% CI = 44.7–65.2) had not received any vaccine. About one third, (31.6%, 95% CI = 22.6–41.8) of the study participants had been fully vaccinated, with close to a quarter (13.3% 95% CI = 7.26–21.6) partially vaccinated. When considering the vaccination status and seroprevalence, out of the 31 fully vaccinated individuals, IgG seropositivity was 81.1% (95% CI = 70.2–96.3) and IgM seropositivity was 35.5% (95% CI = 19.22–54.6). Out of the participants that had not been vaccinated at all, IgG seroprevalence was 70.4% (95% CI 56.4–82.0) with 20.4% (95% CI 10.6–33.5) seropositivity for IgM antibodies. On PCR testing, 33.7% were positive, with 66.3% negative. The 32 positive individuals included 12(37.5%) fully vaccinated, 8(25%) partially vaccinated and 12(37.5%) unvaccinated. SARs-CoV-2 PCR positivity did not significantly predict IgG (p = 0.469 [95% CI 0.514–4.230]) and IgM (p = 0.964 [95% CI 0.380–2.516]) positivity. These data indicate a high seroprevalence of antibodies to SARS-CoV-2 in western Kenya. This suggests that a larger fraction of the population was infected with SARS-CoV-2 within the defined period than what PCR testing could cover.

No abstract

Experiments at Mbaga hills of Siaya County in Kenya were aimed to determine the most effective organic baiting technique for mass harvesting of Macrotermes bellicosus. Around two separate mounds, 5 treatments replicated 3 times, using earthen pot and plastic containers with maize stocks, eucalyptus stems, lantana camara twigs, Napier grass and rice husks, were set up. Termite counts, at 6.00 am and 6.00 pm, and data on temperature and humidity, from a Hobo data logger were collected over the 21 days period. The data were analyzed using Analysis of Variance (ANOVA) at (p=0.05) and Least Significance Difference (LSD) tests. Substrate preference differed significantly (p< 0.05) with highest being maize (2,919). Mean termite count differed significantly by containers (p< 0.05) with highest being earthen pots (1787). Termite count at 6.00 am (2,021) differed significantly (p< 0.05) with at 6.00 pm (1,952). The count further differed significantly by temperature at night (22.1 0 C) and day (30.2±0.13). Finally, count differed by relative humidity (p< 0.05) at night (91.0±0.10) and day (69.1±0.50). Results on the effect of bait type, container type, humidity and temperature on count of termites may have practical, policy and theoretical implications for sustainable agriculture.

Herbals   have been used for decades to treat gastrointestinal infections across the world, including in Tharaka-Nithi County, Kenya. Crude extracts from herbs have long been prescribed by traditional healers for treatment of typhoid, cholera, and shigellosis. However, the effectiveness of extracts obtained using different extraction solvents such as methanol, acetone, and hexane have not fully been evaluated. This study aimed at evaluating the effect of solvents (Ethanol, hexane, and methanol) on the yield of crude extract from plants (Erythrinna abyssinica, Aspilia pluriseta, Vangueria infausta, Ficus sycomorus, and Carissa edulis), assessing the effect of the solvents on extracted active metabolites, and determining the effect of these solvents on extract’s bioactivity against Vibrio cholerae, Shigella flexneri, and Salmonella typhimuriumi and, Escherichia coli that served as a model organism for screening plant extracts against Gram-negative bacteria. Crude extracts were obtained by soaking dried ground plant parts in individual solvents, which were then concentrated by a rotary evaporator. The phytochemical screening to detect plant metabolites was done qualitatively. Bioassays to analyze the efficacy of the plant crude extracts against the microbes were carried out in 4×3×3×5 factorial experiment laid out in a completely randomized design. The determination of bioactivity of herbal extracts was carried out using minimal inhibition concentration and minimum bactericidal concentration methods. Data obtained on the bioactivity assay (Count of the bacteria colony forming units) was analyzed using the Kruskal-Wallis test at α = 0.05, and medians were compared by the Wilcoxon rank sum test in Scientific Analysis System version 9.4. Methanol solvent produced higher quantities of crude extracts for all the herbal samples used with, Vangueria infausta producing the highest extract (5.06g). Most phytochemicals were present in Methanolic extracts compared to hexane and acetone extracts. There was a significant (p < 0.05) difference in the bioactivity of different herbal plants against bacterial pathogens at different concentrations of crude extract. The efficacy of plant extract increased progressively from 100ppm to 1000ppm concentration.  Methanol is recommended for use in the extraction of medicinal plant extracts as it leads to improved potency as compared to hexane and acetone.