Analysis of Indoor Air Microflora of Some Daycare Centres in Ilorin South Local Government Area, Nigeria

Abstract

The microflora of air in ten daycare centres within Ilorin South Local Government Area of Kwara State, Nigeria was investigated by settling plate technique. The plates were exposed for a period of 10 minutes at each sampling point. The counts of bacteria, total coliform and fungi ranged from 10 to 200, 10 to 170 and 6 to 110 cfu/10 minutes respectively. A total of 23 microorganisms comprising 12 bacteria and 11 fungi were isolated in this study. These bacteria were Micrococcus sp., Staphylococcus arlettae, Corynebacterium pseudotuberculosis, Staphylococcus haemolyticus, Corynebacterium kutscheri, Staphylococcus warneri, Staphylococcus aureus, Corynebacterium diphtheriae., Corynebacterium amycolatum, Bacillus pumilus, Corynebacterium matruchotii and Listeria grayi while the fungi were Aspergillus fumigatus, Aspergillus niger, Penicillium chrysogenum, Penicillium sp., Aspergillus flavus, Rhizopus stolonifer, Fusarium oxysporum, Saccharomyces cerevisiae, Alternaria alternata, Aspergillus glaucus and Polyporus sp. The predominant bacterium and fungus in this study were Micrococcus sp. and Aspergillus fumigatus respectively. It can be concluded that the indoor air of the daycare centres used for this study had diverse species of Gram positive bacteria, high occurrence of non-pathogenic bacteria and fungi. Moulds dominate the fungal isolates and some of the bacterial species are commensals found on human body whereas the fungi are environmental in origin. A few pathogenic species were isolated among the bacteria and fungi.