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Medicinal plants have been used as effective approaches to manage multidrug resistant pathogens, including infectious agents that cause nosocomial infections. This study aimed to investigate the antimicrobial potentials of ethanolic extracts of Ricinus comunis, Swietenia mahogani and Crusentia cujete against five multidrug resistant nosocomial pathogens namely; Staphylococcus aureus, Pseudomonas sp., Klebsiella sp., Escherichia coli and Candida sp., which were isolated from hospital fomites. Using standard microbiological methods, fomite swab samples from ward beddings and door handles from the casualty, women, and children ward of Dalhatu-Araf Specialist Hospital, Lafia, Nigeria, were assessed. A total of 251 microbial isolates, consisting of 8 bacterial and 6 fungal genera were recovered. The highest frequency of microbial pathogens was recorded in the casualty unit (98[39%]), followed by the women’s unit (90[36%]), while the children’s ward (63[25%]) was the least contaminated. S. aureus (25[42%]) and Aspergillus sp. (43[72%]) were the most isolated bacteria and fungi; respectively, while Salmonella sp. (7[12%]) and Trichoderma sp. (9[15%]) were the least isolated. However, there were no significantly statistical differences across wards and microbial isolates. The five selected isolates were tested for in vitro susceptibility against several standard antibiotics to check their multiple drug resistance. The tested microorganisms exhibited various levels of multidrug resistance patterns except for Candida sp. which was resistant to two classes of antibiotics (azole group and griseofulvin). On the other hand, Klebsiella sp. was resistant to eight antibiotics of four classes. The ethanolic leaf extract of C. cujete was more effective against all the selected microbial pathogens, while the bark extract of S. mahogani was substantially effective. R. comunis exhibited no inhibitory potential against any of the tested pathogens. All the plant extracts were not as effective against the tested microorganisms as the conventional antibiotics that were used as positive controls. Results obtained indicate the risk of nosocomial infections caused by multidrug resistant pathogens originating from the hospital environment. Good hygienic practices, public awareness on nosocomial infections and further research into ethnomedicine are hereby recommended.

The poultry industry is important in boosting food sustainability of a population; however, the poultry environment and products are susceptible to pathogen contamination arising from poor farm hygienic conditions. This study investigated the prevalence, antimicrobial resistance and virulence profile of Proteus species from the environment and products of four selected poultry farms in Lafia, Nasarawa State. Farm samples (n =216) comprising feed (64), drinking water (64) and swabs from eggshells (88) were collected and analysed for detection of Proteus species using cultural, biochemical and microscopic techniques. Antibiotics susceptibilities of isolates were also determined, and virulence genes were confirmed using Polymerase Chain Reaction. Of the total studied samples, 34.26% (74/216) were positive for Proteus species. Proteus species were more prevalent in drinking water samples (37.84%) and feed samples (33.78%) and least prevalent in eggshells (28.38%). Proteus species (n= 74) comprised P. mirabilis 78% (58/74) and Proteus vulgaris 22% (16/74). P. mirabilis was markedly higher than P. vulgaris in all the four farms sampled. Farms A and D had the highest prevalence of Proteus species, while Farms A and C (80%), and Farm D (25) has the highest prevalence of P. mirabilis and P. vulgaris respectively. The isolates’ prevalence rate within and between farms, sample type, and species was not statistically significantly different (p≥0.05) from the other farms. Isolates were 100% susceptible to Amikacin and showed the highest resistance (25.7%) to tetracycline. Molecular analysis of the virulence genes of Proteus species revealed the presence of rsbA, ureC and luxS virulent genes in all the test isolates. Data generated indicates a high level of multidrug-resistant pathogenic strains of Proteus circulating in poultry farms in Lafia, Nigeria, which potentiates a significant risk of transmission of pathogenic Proteus via the food chain.

This study assessed the survival of some Enterococcus species recovered from the clarifier of two selected wastewater treatment plants in the Eastern Cape Province, South Africa, in the presence of different concentrations of chlorine disinfectant. The bacterial survival, lethal dose and inactivation kinetics at lethal doses were examined. Inactivation of the test bacteria (n = 20) at the recommended dose of 0.5 mg l −1 progressively increased from 3.0–5.8 log reduction within the range of chlorine residual of 0.14–0.45 mg l −1 after 30 min. The bactericidal activity of chlorine increased at higher chlorine dosages with a significant reduction in viability of the bacteria and complete sterilization of the bacterial population was achieved at a lethal dose of 0.75 mg l −1 and 1.0 mg l −1 in 30 min. For the inactivation kinetics, bactericidal activity of chlorine increased with time showing a 3.0–6.8 log reduction in 10 min, 4.0–8.3 log reduction in 20 min and above 7.9 log reduction in 30 min for all test Enterococcus isolates used in this study. Chlorine dose of 0.75 mg l −1 –1.0 mg −1 showed a better disinfecting capacity to effectively reduce the tolerance of Enterococcus species.

This study investigated the survival of Escherichia coli (E. coli) recovered from secondary effluents of two wastewater treatment plants in the Eastern Cape Province, South Africa, in the presence of different chlorine concentrations. The bacterial survival, chlorine lethal dose and inactivation kinetics at lethal doses were examined. The bacterial isolates were identified by 16S rRNA gene sequencing. Comparison of the nucleotide sequences of 16S rRNA gene of bacteria with known taxa in the GenBank revealed the bacterial isolates to belong to Escherichia coli. At the recommended free chlorine of 0.5 mg/L, reduction of E. coli isolates (n = 20) initial bacterial concentration of 8.35–8.75 log was within a range of 3.88–6.0 log at chlorine residuals of 0.14–0.44 mg/L after 30 min. At higher doses, a marked reduction (p < 0.05) in the viability of E. coli isolates was achieved with a greater than 7.3 log inactivation of the bacterial population. Inactivation kinetics revealed a high rate of bacterial kill over time (R2 > 0.9) at chlorine dose of 1.5 mg/L. This study indicates poor removal of bacteria at free chlorine at 0.5 mg/L and a greater efficacy of 1.5 mg/L in checking E. coli tolerance.

This present study assessed the chlorine tolerance of some Citrobacter species recovered from secondary effluents from the clarifiers of two wastewater treatment plants in the Eastern Cape, South Africa. The bacterial survival, chlorine lethal dose and inactivation kinetics at lethal doses were examined. Inactivation of the test bacteria (n = 20) at the recommended dose of 0.5 mg/l for 30 min exposure showed a progressive reduction in bacterial population from 4 to 5 log reduction and residuals ranged between 0.12 and 0.46 mg/l. The bactericidal activity of chlorine increased at higher dosages with a substantial reduction in viability of the bacteria and complete inactivation of the bacterial population at a lethal dose of 0.75 and 1.0 mg/l in 30 min. For the inactivation kinetics, bactericidal activity of chlorine increased with time showing a 3.67–5.4 log reduction in 10 min, 4.0–5.6 log reduction in 20 min and above 6.3 log reductions to complete sterilization of bacterial population over 30 min for all the entire test Citrobacter isolates used in this study. Furthermore, there was a strong correlation (R 2 > 0.84) between bacteria inactivation and increase in contact time. This study appears to have provided support for laboratory evidence of bacterial tolerance to chlorine disinfection at current recommended dose (0.5 mg/l for 30 min), and chlorine concentration between 0.75 and 1.0 mg/l was found to have a better disinfecting capacity to check tolerance of Citrobacter species.