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Background and Objectives: Water is crucial to human existence but may be contaminated with microorganisms, thus making it unfit for consumption. This study aimed to evaluate the physicochemical properties and bacterial loads of selected river waters in Ondo State, Nigeria. Materials and Methods: Ten major rivers were sampled between April and August, 2021. The pH, temperature, total alkalinity, colour, turbidity, electrical conductivity, dissolved oxygen, ammonium, aluminium, organic matters, nitrate levels including the microbial loads were determined according to standard procedures. Confirmation of identified isolates was achieved by API 20E and API 20NE. Results: The turbidity, colour, conductivity, ammonium, and aluminium ranged from 4.3 to 15.2 NTU, 4 to 20 NTU, 123.5 to 580.2 mgL-1, 0 to 3.5 mgL-1, and 0.05 to 1.7, respectively. Most physicochemical parameters showed no significant differences from the WHO permissible limits for drinking water (p > 0.05). The total viable bacterial count in the rivers ranged from 1.5 × 105 to 6.3 × 105 CFUmL-1, while the total coliform count ranged from 1.3 × 103 to 4.8 × 103 CFUmL-1. The predominant bacteria were Escherichia coli and Pseudomonas aeruginosa. Conclusion: This study revealed that the physiochemical properties of the waters were majorly within the WHO permissible standards but with significantly higher bacterial loads.

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Listeria outbreaks and food recalls is on the raise globally. Milk particularly is highly susceptible to Listeria as its production and storage adequately support Listeria growth. The extent of milk contamination with Listeria monocytogenes (Lm) and preventative actions to halt milk associated outbreaks in Africa are unknown. Hence, this study aimed at assessing the national and subregional prevalence of Lm in milk in Africa and identify impacting factors via generalized logistic mixed-effects (GLMEs) and meta-regression modelling. Lm-milk-specific data acquired from primary studies according to standard protocol were fitted using a GLMEs. The GLMEs was subjected to leave-one-study-out-cross-validation (LOSOCV). Factors impacting Lm prevalence in milk were assayed via a 1000-permutation-assisted meta-regression-modelling. The pooled prevalence of Lm in milk in Africa was 4.35% [2.73-6.86] with a prediction interval (PI) of 0.14-59.86% and LOSOCV value of 2.43% [1.62-3.62; PI: 0.32-16.11%]. Western Africa had the highest prevalence [20.13%, 4.13-59.59], then Southern Africa [5.85%, 0.12-75.72], Northern Africa [4.67%, 2.82-7.64], Eastern Africa [1.91%, 0.64-5.55], and there was no record from Central Africa. In term of country, Lm prevalence in milk significantly (p < 0.01) varied from 0.00 to 90.00%. Whereas the Lm prevalence was negligibly different (p = 0.77) by milk type, raw-milk had the highest prevalence [5.26%], followed by fermented-milk [4.76%], boiled-milk [2.90%], pasteurized-milk [1.64%], and powdered-milk [1.58%]. DNA extraction approach did not significantly (p = 0.07) affect Lm prevalence (Boiling [7.82%] versus Kit [7.24%]) as well as Lm detection method (p = 0.10; (ACP [3.64%] vs. CP [8.92%] vs. CS [2.27%] vs. CSP [6.82%]). Though a bivariate/multivariate combination of all tested variables in meta-regression explained 19.68-68.75% (R2) variance in Lm prevalence in milk, N, nation, and subregion singly/robustly accounted for 17.61% (F1;65 = 7.5994; p = 0.005), 63.89% (F14;52 = 4.2028; p = 0.001), and 16.54% (F3;63 = 3.4743; p = 0.026), respectively. In conclusion, it is recommended that adequate sample size should be prioritized in monitoring Lm in milk to prevent spuriously high or low prevalence to ensure robust, plausible, and credible estimate. Also, national efforts/interests and commitments to Lm monitoring should be awaken.

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Laribacter hongkongensis is a human pathogen harboured in food and environmental matrices. This present study aimed to meta-analysed the prevalence of L. hongkongensis in humans, aquatic products, food/non-food animals, and environmental waters to provide update information on the pathogen. Nine electronic databases were systematically searched for articles on L. hongkongensis and a random-effects-model meta-analysis on its prevalence was conducted. Assessment of heterogeneities and publication biases across the studies was determined by using the I2 statistic and Egger's regression/rank correlation tests of funnel plot, respectively. Furthermore, a meta-regression model was explored to unravel factors influencing the prevalence. A total of 39 documents were identified, of which, 33 articles were included as 98 sub-studies for the meta-analysis, and 87 sub-studies for subgroup-analysis. Overall, the prevalence of L. hongkongesis in human, aquatic products, food/non-food animals, and environmental waters was 8.5% (95% CI: 5.8-11.7). The leave-one-out influence analysis yielded a pooled prevalence of L. hongkongensis ranging from 8.1% (95% CI: 5.4-11.3) - 8.8% (95% CI: 5.8-12.3). Sub-group analysis found that the prevalence of L. hongkongensis was highest in Amphibian (54.6%, 95% CI: 41.3-67.6), followed by Pisces (7.9%, 95% CI: 5.3-10.9), Avian (0.5%, 95% CI: 0-5.8), and Mammal (0.5%, 95% CI: 0-3.6). In addition, Egger's regression-test of funnel plot suggests presence of publication (z = 4.2, p < 0.0001) in mammal subgroup. Multivariate meta-regression showed that the prevalence was significantly influenced by source type, class, and identification/detection method with the source type, class, and detection method specifically accounted for 25.49%, 11.28%, and 3.84% of the heterogeneity, respectively. Conclusively, the prevalence of L. hongkongensis decrease in order of Amphibian (54.6%), Pisces (7.9%), Avian (0.5%) and Mammal (0.5%). Aquatic products and environments are essential sources of the pathogen.

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Aims: One of the ways to manage the current coronavirus disease 2019 (COVID-19) pandemic is to monitor the public knowledge, risk perceptions, adherence to preventive measures, and level of preparedness behaviors. This is important in resource-limited countries. This study determined the knowledge and perception regarding COVID-19; adherence to COVID-19 preventive measures; as well as predictors of self-perceived risk of contracting COVID-19 among Nigerian adults. Methods: A cross-sectional study was conducted among Nigerian adults ≥18 years using an online survey. A convenience sampling method was utilized to recruit a total of 1022 study participants. The participants were recruited using the authors' social media networks. Data were analyzed using descriptive and inferential statistics at a 5% level of statistical significance. Results: Generally, a high proportion of respondents had correct knowledge about COVID-19. However, only approximately half (49.8% and 49.9%) had correct knowledge that obesity was a risk factor for COVID-19 and that antibiotics cannot be used to treat COVID-19. Most (84.1%) did not have a self-perceived risk of contracting COVID-19. Most (81.0%) have been avoiding crowded places and 61.3% washed their hands frequently. Predictors of self-perceived risk of COVID-19 were age 40-59 years (OR 2.05, CI 1.217-3.435), ≥ 60 years (OR 4.68, CI 1.888-11.583), and visiting crowded places (OR 2.27, CI 1.499-3.448). Conclusion: Our study recommends more rigorous public health education aimed at improving COVID-19 outbreak response in Nigeria. In addition, physical and social distancing should be emphasized across all age groups with additional focus on the older population.

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The human norovirus (HNoV), on a global scale, is the prevailing cause of contagious viral gastroenteritis outbreaks, with more than 200 000 deaths annually. This study aimed at assessing specific prevalence of HNoV pollution in different water sources and their roles in the dissemination of HNoV, with a view to refocus water sources and sewage management options for policy making towards public health safety. In this regard, we conducted a systematic review and meta-analysis (SR/MA) of the prevalence of HNoV in water sources. We searched PubMed, Google Scholar, Scopus and Web of Science for studies on HNoV prevalence in water sources without temporal restriction, till January 30, 2021. We conducted a random-effects meta-analysis of the HNoV prevalence and stratified the study by water type, continent, gross national income (GNI) group and genogroup. Further, a mixed-effects meta-regression model was performed for sensitivity analysis. The literature search identified 61 studies on water source-based HNoV (WsHNoV) prevalence. The pooled WsHNoV prevalence was 31.7% (95%CI: 25.1-38.5) but varied according to water sources types; river water showing the highest estimate at 43.5% (95%CI: 33.9-53.4), followed by estuarine water (30.6%, 95%CI: 12.5-52.2), composite water (27.9%, 95%CI: 13.5-44.9), marine water (25.9%, 95%CI: 10.0-45.6), groundwater (19.7%, 95%CI: 9.4-32.3) and lake water (2.2%, 95%CI: 0-25.8). Further, the findings indicated the highest WsHNoV prevalence in Africa as 55.9% (95% CI: 28.2-81.9), followed by Asia (31.6%, 95% CI: 22.3-41.6), Europe (29.8%, 95% CI: 17.9-43.2), North America (27.7%, 95% CI: 11.2-47.6) and South America (27.1%, 95%CI: 0.09-49.4). The WsHNoV prevalence stratified by GNI group was 40.6% (95%CI: 27.9-53.9) in middle-income countries and 28.7% (95%CI: 21.7-36.1) in high-income countries respectively. The prevalence of GI, GII and GI & GII genogroup in natural water was 16.4% (95%CI: 12.0-21.3), 20.6% (95%CI: 15.7-25.8) and 12.8% (95%CI: 6.9-20.6) respectively. Evidently, prevalence of the HNoV genogroup in water sources mirrors the pattern of HNoV gastroenteritis and GII genogroup dominance worldwide. In conclusion, public health efforts against waterborne diseases should prioritize water resource/sewage management options and policies towards ardent water sources pollution prevention.

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Chlorine is the commonest and cheapest disinfectant used in drinking water and wastewater treatment at household, municipal and industrial levels. However, the uprising of microbial chlorine resistance (MCR) pose critical public health hazard concerns; because, its potentiate exposure to difficult-to-treat resistant pathogens. Therefore, this study aimed at evaluating the burden of MCR in drinking water/wastewater treatment and distribution systems (DWWTDS) via science mapping of research productivity (authors, countries, institutions), thematic conceptual framework, disciplines, research networks and associated intellectual landscape. MCR data were mined from Scopus and Web of Science based on optimized algorithms with the root key term "chlorine* resistant*'' and analysed for pre-set indicator variables. Results revealed 1127 documents from 442 journals and 1430% average growth rate (AGR) of research articles from 2017 to 2019 on MCR. Country-wise, the USA (n = 299), China (n = 119), and Japan (n = 43) ranked in the 1st, 2nd, and 3rd positions respectively, among the top participating countries in MCR research. MCR research had considerable performance in public health and sustainable concern subjects namely, Environmental Sciences & Ecology, Engineering, Microbiology, Water Resources, Biotechnology & Applied Microbiology, Food Science & Technology, Public, Environ & Occupational Health, Chemistry, Infectious Diseases, and Marine & Freshwater Biology; and with noticeable AGR in Environmental Sciences & Ecology (330%) and Infectious Diseases (130%). The study found biofilm-related thrusts (n = 90, 270% AGR) as main research hotspots on MCR. Overall, the study identified and discussed four important thematic areas of public health challenges in MCR that could promote increasing waterborne diseases due to (re)emerging pathogens, enteric viruses and dissemination in DWWTDS. In conclusion, this study provides comprehensive overview of the growing burden of MCR in DWWTDS and standout as a primer of information for researchers on MCR. It recommends direct, intentional and integrated research priorities on MCR to overcome accompanying public health and environmental threats. In addition, chlorine resistance in waterborne fungi have not received research attention. Research activities related to fungal chlorine resistance will be an invaluable future direction in DWWTDS and guide against exposure to waterborne pathogenic fungi and mycotoxins. It is unknown whether chlorine resistance can be acquired by horizontal gene transfer in microorganisms and future research should elucidate this important thrust.

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Toxoplasmosis is a global health threat in which occurrence in pregnant women poses grave consequences to fetal wellbeing. Studies on prenatal Toxoplasma gondii infection are generally limited in sub-Saharan African countries, including Nigeria. The risk of transmission of toxoplasmosis is very high in Nigeria due to the favourable climatic conditions and prevailing behavioural and socio-economic factors that could aid transmission. Currently, there are no systematic and organized procedures for diagnosis and treatment of maternal toxoplasmosis in Nigeria. These conditions forecast possible unabated transmission in many areas and exponential impact on associated adverse events of the disease during pregnancy. This paper highlights the importance of early diagnosis and treatment during pregnancy which may forestall subsequent development of infection in children delivered by infected mothers. Inclusion of toxoplasmosis control policy in the routine antenatal care of pregnant women is therefore strongly recommended.

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