Bacterial population of environmental surfaces in child-care centres in Omoku and Port Harcourt, Nigeria

Abstract

The aim of this study was to enumerate the bacterial population isolated from environmental surfaces in child-care centres in Omoku and Port Harcourt, Nigeria. Four child-care centres in Omoku and Four from Port Harcourt, Nigeria were selected for the study and samples from different environmental surfaces (Table, play mat, toilet seat, feeding area, diaper changing area, toys, window and door handle surfaces) using sterile swab sticks moistened with sterile peptone water. Aliquots of 0.1 ml from the 103 dilutions were inoculated on agar plates of different culture media using the spread-plate method. The following culture media were used for the inoculation; Mannitol salt agar, Eosine methylene blue agar, MacConkey agar, Salmonella-Shigella agar, and Nutrient agar. The inoculated media were incubated at 35 °C for about 24 hours. An indirect cell count was performed in which the number of colonies produced on the various culture media plates were counted and recorded, and the information was used to calculate the amount of microorganisms in the original sample. The total heterotrophic bacterial counts of diapers changing surfaces in four schools located in Omoku ranged from 3.6×104 to 7.7×104 CFU/cm2 while those obtained from schools in Port Harcourt ranged from 2.2×104 to 6.1×104 CFU/cm2. The total coliform, faecal coliform, Salmonella-Shigella and staphylococcal counts of diapers changing surfaces in Omoku ranged 3.1×104 to 3.7×104, 2.8×102 to 3.9×102, 0.3×103 to 1.4×103, and 0.4×103 to 3.5×103 CFU/cm2 respectively. While that of Port Harcourt ranged from 0.4×104 to 3.3×104, 0.8×102 to 5.0×102, 0.8×103 to 4.7×103 and 3.8×103 to 18.5×103 CFU/cm2 respectively. The mean faecal coliform counts of door handle from schools in Omoku ranged from 0.9×103 to 4.8×103 CFU/cm2, while those from schools in Port Harcourt ranged from 0.2×103 to 0.32×103 CFU/cm2. The total heterotrophic bacterial load of the feeding areas of schools in Omoku ranged from from 0.7×104 to 1.6×104 CFU/cm2 while the mean range of 8×104 to 1.3×104CFU/cm2 was recorded for schools in Port Harcourt. The total heterotrophic bacterial count of play mats of schools located in Omoku ranged from 0.1×104 to 4.3×104 CFU/cm2, while that of Port Harcourt ranged 0.3×104 to 0.40×104 CFU/cm2. There were significant differences (p< 0.05) in the counts of the total heterotrophic bacteria for tables, Salmonella-Shigella counts for toilet seats and total staphylococcal counts for both toilet seats and toys. The faecal coliform bacteria of playmat and window surfaces showed no variance from both schools in Omoku and Port Harcourt. These results revealed that the high bacterial prevalence of these bacterial isolates in environmental surfaces of child-care facilities especially in faecal coliform and staphylococci is of public health importance especially as they could pose danger. Good hygiene including washing of hands and mopping of floors with disinfectants and clean water is highly recommended.