Prevalence of Staphylococcus spp. from human specimens submitted to diagnostic laboratories in South Africa, 2012-2017.

Background: Although staphylococci are commensals of the skin and mucosa of humans and animals, they are also opportunistic pathogens. Some coagulase-negative Staphylococcus spp. (CoNS), such as S. haemolyticus and S. epidermidis, are reported to be zoonotic.

Objectives: The prevalence of coagulase positive (CoPS), CoNS and coagulase-variable Staphylococcus spp. isolated from human clinical cases in South Africa was investigated.

Method: Retrospective records of 404 217 diagnostic laboratory submissions from 2012 to 2017 were examined and analysed in terms of time, place and person.

Results: Of the 32 different species identified, CoPS were the most frequently isolated (74.7%), followed by CoNS (18.9%). Just over half (51.2%) of the Staphylococcus isolates were from males, while females contributed 44.8%. Patients aged 0-4 years contributed the most (21.5%) isolates, with the highest number coming from KwaZulu-Natal (32.8%). Urinary specimens accounted for 29.8% of the isolates reported. There was no variation in the number of Staphylococcus isolates reported in the autumn (25.2%), winter (25.2%), spring (25.1%) and summer (24.5%) seasons.

Conclusion: This study demonstrated the diversity of Staphylococcus spp. isolated from humans and the magnitude of infection, with the most predominant species being S. aureus and S. epidermidis.

Contribution: Although most isolates were CoPS, the isolation of CoNS seen in this study suggests a need to improve infection control measures in a South African context. More research is needed to investigate the determinants of the observed variations in the study.