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Mwansa, M.

Publications and source records attributed to Mwansa, M..

2 recordsLinked to original sources
bioRxiv2020

Antibiotic-resistant Salmonella species and Escherichia coli in broiler chickens from farms, abattoirs and open markets in selected districts of Zambia

Salmonella species and Escherichia coli are major bacterial enteropathogens of global public health importance that cause foodborne diseases, thereby contributing to increased human morbidity and mortality. Both pathogens have also been found to contribute towards the spread of antimicrobial resistance through the food chain, especially in poultry. The aim of this study was to determine the occurrence of antibiotic-resistant Salmonella sp. and E. coli in broiler chickens at farm level, abattoirs and open markets in selected districts of Zambia. A cross-sectional study was undertaken in seven districts of Zambia to determine the resistance profiles of Salmonella sp. and E. coli obtained from broiler chickens at farms, abattoirs and open markets. A total of 470 samples were collected, including litter, cloacal swabs and carcass swabs. Samples were inoculated into buffered peptone water, sub-cultured onto MacConkey and Xylose Lysine Deoxycholate agar plates. Identification of Salmonella sp. and E. coli was done using the API-20E kit and confirmation by 16S rDNA sequencing. Confirmed isolates were tested against a panel of 10 antibiotics using the Kirby-Bauer disc-diffusion method and interpreted according to the Clinical Laboratory Standards Institute guidelines. Analysis of the antibiotic susceptibility test results was done using WHONET 2018 software. Overall, 4 Salmonella spp. and 280 E. coli were isolated. One of the Salmonella sp. was resistant to ampicillin (25%), amoxicillin/clavulanic acid (25%) and cefotaxime (25%). E. coli antibiotic resistance was highest to tetracycline (81.4%) and lowest to imipenem (0.7%). The antibiotic susceptibility profile revealed 55% (154/280) multidrug resistant E. coli, with the highest multidrug resistance profile (20.7%) in the ampicillin-tetracycline-trimethoprim/sulfamethoxazole drug combination. Furthermore, 4.3% (12/280) of the isolates showed Extensive Drug resistance. The levels of antimicrobial resistance to E. coli and Salmonella observed in market-ready chickens is of public health concern.View Full Text

scientific communication and education↗
bioRxiv2017

Multidisciplinary field research in Kabwe, Zambia, towards better understanding of lead contamination of the city - A short report from a field survey

Heavy metal contamination is a serious issue in many post-mining regions around the world. Kabwe town, Zambia, is known as one of the most polluted cities in the world, where high lead (Pb) levels have been reported in soils, plants, animals and human blood. Multidisciplinary approaches are critically needed to understand the current situation and to remediate the polluted area. In the current research, a large-scale preliminary field survey was performed to understand the current situation in Kabwe and to plan future mitigation approaches. Three aspects were mainly observed; 1) plant communities during the dry season in Kabwe city, 2) spectral images of the land surfaces in various locations in Kabwe and 3) Pb concentrations in soils and water. Overall, >15 different plant species were observed and many of them maintained their green colour even during the dry season. Some tree species, for example, Caesalpiniaceae and Fabaceae families may be utilised as phytostabilization approaches although their impacts on the soil Pb mobility should be further studied. For the spectral images, we used a handmade portable spectrometer, and our obtained spectral images showed typical curves observed from soils. These data may be used to understand the distribution of different soil types in this area, using aboveground images such as satellite images. For Pb concentrations in soils, extremely high total Pb levels (>1,000 ppm) was observed only within 2 km from the mining site. There was a weak but a positive correlation between the total and soluble Pb thus further study should also focus on the mobility of Pb from soils to plant ecosystems.

ecology↗