There is presently no information on the occurrence, abundance and diversity of airborne bacteria in Botswana hospitals. In addition, there is also growing concern in the global spread of antibiotic resistant bacterial pathogens that continue to emerge and pose a huge challenge to human health. This study was aimed at; 1) determining the occurrence, relative abundance and diversity of airborne bacterial species. 2) identifying the antibiotic resistance patterns of bacterial isolates and 3) finding the correlation between the meteorological conditions and the bacterial concentrations in the hospital’s paediatric and operating theatre wards in Botswana.
Air impaction method was applied for the collection of airborne bacteria on selective media, antibiotic resistance was determined by screening isolates for resistance phenotypes and PCR was applied for detection of resistance genes to clinically relevant antibiotics. The assessment of total airborne bacteria in hospital units revealed high abundance of airborne bacteria in paediatric wards than in the operating theatres. The highest bacterial concentrations were observed at the paediatric wards in Palapye (PPH; 7.9 x102 CFU/m3), Maun (LMH; 6.4 x102 CFU/m3) and Francistown (NRH; 5.8 x102 CFU/m3). Diverse airborne bacterial species were observed with high concentration recorded for Pseudomonas species in all three hospitals’ units. The frequency of antibiotic resistance genes and the integron mobile element detected in bacterial isolates were; dfr1 (36%), mph(A) (26%), ermC (12%), strB (10%) and intI1 (16%). The study provide evidence suggesting air in hospitals’ units as a hotspot for potentially pathogenic bacteria and antibiotic resistance genes, hence the need to develop surveillance tools for monitoring the movement of airborne bacteria in operating theatre and paediatric wards in order to mitigate possible spread of nosocomial infections.
Keywords: Airborne bacteria, antibiotic resistance genes, operating theatre, paediatric, human health