Abstract

BACTERIA COLONIZATION OF THE NASOPHARYNX OF STUDENTS IN A TERTIARY INSTITUTION SETTING

Ademola Adebobola Yetunde, Omo-Omorodion Blessing Itohan, Ako-Nai Kwashie Ajibade* and Adegun Busayo Roseline

Abstract

Background: The nasopharynx harbours various diverse microflora in children and can be complex ecosystem. Most of these flora are commensals in adults which are not often investigated. The study analysed such diversity among apparently healthy students, the antibiotic susceptibility and products of resistance between September 2015- February 2016. Methods: Two hundred (200) apparently healthy students aged 16-30 years were recruited for the study. Each sample was collected from participant’s pharynx using a sterile cottontipped applicator that was initially dipped in sterile normal saline and introduced into sterile thioglycollate fluid media. All such samples were incubated at 37oC aerobically for 24 hours for growth. Duplicate samples were prepared for anaerobes and incubated with 5% CO2 in anaerobic jars and further studied. Antibiotic susceptibility tests were carried out by the Kirby Bauer disc diffusion method using the Mueller Hinton as plating agar. Molecular characterization of resistant and virulence genes was carried out by polymerase chain reaction (PCR). Results: The study revealed 39% of the study population aged 19-21 years, had the highest carriage rate. Pathogenic S. aureus constituted 52(33.55%), streptococci 7(4.52%). 79 predominant pathogens were recovered with high resistance to the beta lactams, 70(88.62%) compared to 9(11.39%) to ciprofloxacin and 11(13.92%) to gentamycin. Of the 12 S. aureus isolates amplified and electrophoresed, 9 isolates presented the nuc gene, three isolates carried the aac-3-iv resistant gene while7 isolates carried the mecA resistant gene. However, none of the isolates carried the Luk-pv gene. Conclusion: The study revealed the extent to which the beta lactams antibiotics 88.62% were ineffective compared to 13.92% gentamycin and 11.39% ciprofloxacin.

Keywords: Nasopharynx, pathogenic bacteria, antibiotics and resistance.