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The microbial quality of two groundwater sources (well and borehole) and associated risks were quantitatively assessed. Water samples from the selected borehole and well were collected over a period of 12 weeks (n = 48). The concentrations of Escherichia coli, faecal coliforms, Salmonella, Shigella, Clostridium, Bifidobacterium and Campylobacter were determined using standard microbiological methods, which involve the use of a membrane filter technique. The water samples were filtered through a 0.45 μm membrane filter using vacuum pump pressure and plated on selective agar for the bacteria under test. The number of colonies of the bacterial growth observed after the incubation period was counted and recorded. The physicochemical properties of the water were determined using standard methods. The risk of Salmonella, Shigella, Clostridium and Campylobacter infections resulting from the ingestion of water from the borehole and well was estimated. The results showed that the levels of enteric bacteria in the borehole were higher than those in the well. The mean levels of E. coli in water from the borehole and well were 3.3 and 1.7 log10 cfu/100 ml, respectively, and exhibited a negative relationship with salinity (r = −0.53). The estimated risks of infection associated with the pathogens in water from the borehole and well were greater than the acceptable risk limit of 10−4 and followed this order Clostridium<Salmonella<Campylobacter<Shigella. The findings of this study suggest recent and continuous faecal contamination of the two groundwater sources, thus exposing the residents relying on the water for drinking to potential risks of gastrointestinal infections.

Aim This study set out to determine whether phage‐based indicators may provide a ‘low‐tech’ alternative to existing approaches that might help maintain the microbial safety of shellfish and their overlying waters. Methods and Results Mussels and their overlying waters were collected biweekly from an estuary in southeast England over a 2‐year period (May 2013–April 2015) (n = 48). Levels of bacterial indicators were determined using membrane filtration and most probable number methods and those of bacteriophages were determined by direct plaque assay. The detection of adenovirus was determined using real‐time polymerase chain reaction. The results revealed that somatic coliphages demonstrated the most significant correlations with AdV F and G in mussels (ρ = 0·55) and overlying waters (ρ = 0·66), followed by GB124 phages (ρ = 0·43) while Escherichia coli showed no correlation with AdV F and G in mussels. Conclusion This study demonstrates that the use of somatic coliphages and GB124 phages may provide a better indication of the risk of adenovirus contamination of mussels and their overlying waters than existing bacterial indicators. Significance and Impact of the Study Phage‐based detection may be particularly advantageous in low‐resource settings where viral infectious disease presents a significant burden to human health.

This study was carried out to determine the level of enteric bacteria in two surface water sources (river and stream) commonly used for domestic, recreational and agricultural purposes in Akure, Nigeria. This is to gain a better understanding of the level of faecal pollution of the water sources and the potential health risks associated with usage of the waters for human activities. Water samples were collected from the river and the stream from May to September, 2019 (n = 24). The concentration of enteric bacteria in the water samples were determined using membrane filtration technique while the physicochemical characteristics of the water samples were determined using standard method. Results revealed that the concentration of E. coli ranged from 3.00 to 4.78 log10 cfu/100ml and 3.48 to 5.75 log10 cfu/100ml in water samples from the river and stream respectively; Bifidobacterium ranged from 4.18 to 5.00 log10 cfu/100ml and 3.87 to 4.66 log10 cfu/100ml in water samples from the river and stream respectively; and Salmonella ranged from 3.30 to 4.30 log10 cfu/100ml and 2.60 to 4.32 log10 cfu/100ml in water samples from the river and stream respectively. Water temperature ranged from 22.1 to 28.5 °C and 23.64 to 25.56 °C in the river and stream respectively; and turbidity ranged from 12.28 to 29.11 NTU and 17.07 to 61.80 NTU in the river and stream respectively. Spearman's rank correlation showed that Salmonella had positive relationship with temperature (r = 0.556) in water samples from the stream whereas Bifidobacterium exhibited positive relationship with dissolved oxygen (r = 0.557) in water samples from the river. Whilst the stream appeared to have a higher turbidity than the river, the level of enteric bacteria in the river were more than those in the stream. Based on microbiological water quality categories, the findings from this study demonstrated that the level of enteric bacteria in the river and stream suggests strong faecal pollution that may pose potential risks of diarrheal diseases to humans. Water from these two surface water sources must be treated before use in order to protect human health.

The effect of Aloe vera gel on microorganisms associated with the deterioration of sweet orange (Citrus sinensis) fruits was investigated. Sweet orange fruit was obtained from selected markets and farm in Akure, Nigeria. Microorganisms associated with the deterioration were identified using microbiological techniques. A total of nine fungi and six bacteria were isolated from the orange fruits. Fungal isolates include Aspergillus flavus, A. niger, Fusarium oxysporium, Penicillum digitatum, Rhizopus stolonifer, Penicillium italicum, Mucormucedo, Saccharomyces cerevisiae and Geotrichium candidum, while the bacterial isolates were Staphylococcus aureus, Escherichia coli, Bacillus cereus, B. substilis, Serratia marcesens and Pseudomonas aeruginosa. The average fungal counts ranged from 2.4 × 10 3 cfu/g to 5.3 × 10 3 sfu/g and bacterial count ranged from 1.4 × 10 5 cfu/g to 3.6 × 10 5 cfu/g. Pathogenicity test revealed that Rhizopus stolonifer, Penicillum

This study was carried out to examine the sanitary quality of overlying waters in an earthen pond containing African catfish (Clarias gariepinus) in both wet and dry seasons. Water samples were collected twice weekly at different times of the day (i.e., morning and afternoon) from the earthen pond in Akure, Nigeria in August, September 2016, and February, March 2017 (n=48). Levels of faecal indicator bacteria were determined using membrane filtration method and physicochemical properties (such as temperature, pH, salinity etc.) of the overlying water samples were determined using standard methods. The results revealed that the concentration of E. coli in the overlying waters ranged from 0.78 to 1.40 Log10 CFU 100 ml-1 in morning samples and 0.85 to 1.38 Log10 CFU 100 ml-1 in afternoon samples while the concentration of faecal coliforms in the overlying waters ranged from 1.30 to 1.86 Log10 CFU 100 ml-1 in morning samples and 1.26 to 1.88 Log10 CFU 100 ml-1 in afternoon samples. Faecal coliforms showed the highest prevalence in both seasons compared to E. coli and intestinal enterococci and their levels were greater in the wet periods than the dry periods. The findings from this study suggest that the sources of faecal contamination of the overlying waters in the earthen pond originate mainly from non-human sources and the adoption of microbial source tracking techniques would further elucidate the appropriate management and mitigation strategies to control faecal contamination of the overlying waters in the earthen pond especially for human health protection.

Background: Hospital wastewaters contain blends of inorganic, natural constituents and contaminants that carry significant health risk when released directly into the environment. The aim of this study is to investigate the correlation between faecal indicator bacteria in diarrheagenic stools and wastewaters generated in University of Medical Sciences Teaching Hospital complex, Akure, Nigeria.Methodology: Quantification of faecal indicator bacteria was carried out on diarrheagenic faecal samples collected from 55 hospitalized patients and 68 wastewater samples from the medical laboratory science and laundry units of the hospital over of period of 12 weeks. Standard membrane filtration technique was performed using membrane intestinal enterococcus (m-ENT), membrane faecal coliform (m-FC), membrane lauryl sulphate (MLSA), eosin methylene blue (EMB) and Salmonella-Shigella (SS) agar plates, which were incubated at 37ºC for 24 hours (MLSA, EMB and SSA), 44ºC for 24 hours (m-FC); and 37ºC for 48 hours (m-ENT). Bacterial colonies on agar plates were counted and expressed as colony forming units (CFU) per 100ml of diarrheagenic stool and wastewater. Pearson’scorrelation analysis was used to determine the relationship between the level of faecal indicator bacteria in diarrheagenic stools and wastewaters at p<0.05 level of significance (and 95% confidence interval).Results: The faecal coliform counts (log 10 CFU/100ml) ranged from 1.18 to 1.54 in diarrheagenic stools, 1.32 to1.64 in laboratory wastewater and 1.08 to 2.19 in laundry wastewater. Escherichia coli count (log 10 CFU/100ml) ranged from 1.08 to 1.40 in diarrheagenic stools, 1.20 to 1.86 in laboratory wastewater and 0.30 to 1.81 in laundry wastewater. Intestinal enterococci count (log 10 CFU/100ml) ranged from 0 to 0.30 in diarrheagenic stools, 0.78 to 0.90 in laboratory wastewaters and 0.48 to 1.11 in laundry wastewaters. Pearson’s correlation co-efficient showed that all the faecal indicator bacteria count in diarrheagenic faecal samples exhibited positive correlation with those in laboratory wastewaters, but not with those from laundry wastewaters.Conclusion: The findings suggest that diarrheagenic stools should be properly disinfected after the performance of laboratory tests to prevent transmission of potential pathogens, and wastewater generated from hospitals should be treated prior to discharge into the environment, to prevent possible infections in the community. Keywords: Correlation, faecal indicator bacteria, public health, transmission, wastewater

This study was aimed at determining the antibacterial activities of Andrographis paniculata on methicillin and vancomycin resistant enteric bacteria isolated from River Owena, Owena, Nigeria. Water samples were collected weekly from River Owena over a period of six weeks (n = 6). The bacteriological evaluation of the water samples was carried out using standard microbiological method.  A. paniculata leaf and stem extracts were prepared using the polar (i.e., methanol) and nonpolar (i.e., n-hexane) solvents. The phytochemical constituents and antibacterial activity of all the extracts of A. paniculata leaf and stem were investigated using standard methods. Results revealed that methanol extracts from A. paniculata contained the maximum amount of phytochemicals when compared to that of the n- hexane extracts. Salmonella and Shigella were both resistant to vancomycin, while they were only susceptible to methicillin once throughout the sampling week.  The methanol extracts from A. paniculata showed higher antibacterial activity against the targeted bacterial isolates of enteric origin which include E. coli, faecal coliforms, Shigella, Salmonella and intestinal enterococci. The methanol leaf extract of A. paniculata showed the maximum antibacterial activity against E. coli, Salmonella, Shigella, intestinal enterococci and faecal coliform with zones of inhibition 29.0 mm, 26.00 mm, 21.3 mm, 21 mm and 19 mm respectively. The methanollic stem extract of A. paniculata showed a maximum antibacterial activity against Salmonella with zone of inhibition of 25 mm while n-hexane stem extract exhibited a maximum zone inhibition of 17.6 mm against Salmonella. The minimum inhibitory concentration (MIC) value for all the A. paniculata extracts was at a concentration of 12.5 – 50 ml. The pH of the water ranged from 6.50 to 6.90, temperature ranged from 26 to 31°C. The findings from this study demonstrated that River Owena is highly contaminated with faecal materials and that leaf and stem extracts of A. paniculata may be used as antibacterial agents against methicillin and vancomycin resistant bacteria of enteric origin.