Antimicrobial Susceptibility Profiles and Molecular Characterisation of <i>Staphylococcus aureus</i> from Pigs and Workers at Farms and Abattoirs in Zambia
Mulemba Tillika Samutela,
Bruno Stephen July Phiri,
Edgar Simulundu,
Geoffrey Kwenda,
Ladslav Moonga,
Eugene C. Bwalya,
Walter Muleya,
Therese Nyirahabimana,
Kaunda Yamba,
Henson Kainga,
Simegnew Adugna Kallu,
Innocent Mwape,
Andrew Frey,
Matthew Bates,
Hideaki Higashi,
Bernard Mudenda Hang'ombe
Affiliations
Mulemba Tillika Samutela
Department of Biomedical Sciences, School of Health Sciences, University of Zambia, Lusaka 10101, Zambia
Bruno Stephen July Phiri
Central Veterinary Research Institute, Lusaka 10101, Zambia
Edgar Simulundu
Department of Disease Control, School of Veterinary Medicine, University of Zambia, Lusaka 10101, Zambia
Geoffrey Kwenda
Department of Biomedical Sciences, School of Health Sciences, University of Zambia, Lusaka 10101, Zambia
Ladslav Moonga
Department of Paraclinical Studies, School of Veterinary Medicine, University of Zambia, Lusaka 10101, Zambia
Eugene C. Bwalya
Department of Clinical Studies, School of Veterinary Medicine, University of Zambia, Lusaka 10101, Zambia
Walter Muleya
Department of Biomedical Sciences, School of Veterinary Medicine, University of Zambia, Lusaka 10101, Zambia
Therese Nyirahabimana
Department of Biomedical Sciences, School of Veterinary Medicine, University of Zambia, Lusaka 10101, Zambia
Kaunda Yamba
Department of Disease Control, School of Veterinary Medicine, University of Zambia, Lusaka 10101, Zambia
Henson Kainga
Department of Disease Control, School of Veterinary Medicine, University of Zambia, Lusaka 10101, Zambia
Simegnew Adugna Kallu
Department of Disease Control, School of Veterinary Medicine, University of Zambia, Lusaka 10101, Zambia
Innocent Mwape
Center for Infectious Disease Research Zambia, Lusaka 10101, Zambia
Andrew Frey
Department of Cell Biology, Microbiology and Molecular Biology, University of South Florida, Tampa, FL 33620, USA
Matthew Bates
School of Life & Environmental Sciences, University of Lincoln, Lincolnshire LN6 7TS, UK
Hideaki Higashi
Division of Infection and Immunity, International Institute for Zoonosis Control, Hokkaido University, Sapporo 001-0020, Japan
Bernard Mudenda Hang'ombe
Department of Paraclinical Studies, School of Veterinary Medicine, University of Zambia, Lusaka 10101, Zambia
Pigs have been shown to be a reservoir for recently emerging livestock-associated Staphylococcus aureus (LA-SA), including methicillin resistant strains in many countries worldwide. However, there is sparse information about LA-SA strains circulating in Zambia. This study investigated the prevalence, phenotypic and genotypic characteristics of S. aureus from pigs and workers at farms and abattoirs handling pigs in Lusaka Province of Zambia. A total of 492 nasal pig swabs, 53 hand and 53 nasal human swabs were collected from farms and abattoirs in selected districts. Standard microbiological methods were used to isolate and determine antimicrobial susceptibility patterns of S. aureus. Polymerase Chain Reaction was used to confirm the species identity and detect antimicrobial resistance and virulence genes of isolates, whereas genetic diversity was evaluated using spa typing. Overall prevalence of S. aureus was 33.1%, 37.8% for pigs and 11.8% for humans. The isolates were resistant to several antibiotics with resistance ranging from 18% to 98% but were all susceptible to vancomycin. Typical LA-SA spa types were detected. The presence of plasmid mediated resistance genes such as tetM (12.8%), other resistance determinants and immune evasion cluster genes among the isolates is of great public health concern. Thus, continuous surveillance of S. aureus using a “One health” approach is warranted to monitor S.aureus infections and spread of antimicrobial resistance.
