Microbial flora of the respiratory tract and skin of artisanal municipal solid waste handlers in Aba, Abia State, Nigeria

Municipal solid waste handling carries occupational risk for waste handlers due to exposure to diverse microorganisms and hazardous substances that cause respiratory and skin infections. A cross-sectional study was carried out, and 150 respondents were recruited using a simple random sampling technique. The sociodemographic characteristics, health-related complaints, health-seeking behaviour and the bacterial and fungal microflora of the respiratory tract and skin of artisanal municipal solid waste handlers and some controls in Aba, Nigeria, were determined using a mixed methods research design, involving the use of interviewer-administered structured questionnaires and conventional culture techniques. We analysed the data using IBM SPSS version 25. The results are presented in tables as frequencies and percentages. The majority of artisanal municipal solid waste handlers in Aba are male (95%). Their mean age is 30 years, and the age group of 21–40 years constitutes the highest proportion (65%) of the workforce. Health-related complaints were higher (95%) among the waste handlers compared to the control subjects (4%). The findings show a high prevalence of respiratory (57%), eye (34%) and skin (87%) complaints among the waste workers, compared to 6%, 0% and 2%, respectively, among the control subjects. Seventy-eight (78%) of the waste handlers indulge in self-medication via over-the-counter (OTC) drugs; 17 (17%) access diagnostic laboratories and only 4 (4%) visit hospitals for treatment, as compared to the control subjects, who recorded 1 (2%) for OTC drugs, 46 (92%) for laboratories and 2 (4 %) for hospitals. Acquisition (15%) and use (3%) of personal protective equipment (PPE) were very low amongst the waste handlers. A total of 704 bacterial isolates and 191 fungal organisms were isolated from the study subjects. Among the waste handlers, the percentage distribution of bacteria was almost the same at both sites: respiratory tract, 241 (49.9%) and skin, 242 (50.1%), compared to the control subjects’ respiratory tract, 105 (47.5%) and skin, 116 (52.5%), which showed a slight difference between the sites. S. epidermidis (24%) and B. cereus (13%) were predominant in the respiratory tract, whereas S. aureus (29%) and S. epidermidis (19%) predominated the skin of the waste handlers. Similarly, S. aureus (34.3%) and B. cereus (20.9%) were predominant in the respiratory tract, while B. cereus (37.9%) and S. epidermidis (18.1%) predominated the skin of the control subjects. Candida spp. was the most predominant fungus in the respiratory tract (81.4%) and skin (42.9%) of the waste handlers, as well as in the respiratory tract (85%) and skin (78%) of the controls. The presence of the isolated bacteria and fungi in increased proportions in the waste handlers may be attributed to occupational exposure through direct contact with waste, inhalation of organic dust laden with biological agents and the poor working conditions of the waste handlers. Health education and improvements in working conditions are necessary to mitigate the occupational challenges of waste handlers.