Assessment of Gram-Positive Bacteria on Door Handles of Service Offices at some Universities in Khartoum State

Abstract

Bacterial contamination of door handles has been an area of major concern. The objective of this study was to assess Gram-positive bacteria on the door handles of service offices at Sudanese universities in Khartoum State. The study was conducted during the period August-September 2014. A total of 200 office door handles were sampled in aseptic manner using sterile cotton swabs moistened in sterile nutrient broth. The swabs were used to inoculate nutrient agar plates which were incubated at 37ºC for24- 48 hours. Bacterial load was assessed semi-quantitatively at the end of incubation period. Gram-positive bacteria were identified by standard bacteriological methods, including colonial morphology, Gram stain, and biochemical tests. The results revealed that 87(43.5%) swabs yielded bacterial growth. These were obtained from Alneelain University 40(45.98%), Sudan university of science and technology (SUST) 24(27.58%) and University of Khartoum 23(26.44%). The average of bacterial load estimated at different universities was as follows; University of Alneelain high (++++), SUST and Khartoum University moderate (+++). Gram-positive bacteria were recovered from 32 samples investigated; Seven from University of Khartoum, ten from SUST and fifteen from Alneelain University. The most prevalent was S. aureus, followed by Bacillus spp., but considerable number of other staphylococci was also recovered. The study concluded that the load of bacterial contamination of door handles is considerable. Potentially pathogenic bacteria exist in the office door knobs. Further studies are required to validate the results of the present study are recommended.