Associated risk factors and pulsed field gel electrophoresis of nasal isolates of Staphylococcus aureus from medical students in a tertiary hospital in Lagos, Nigeria

Abstract

Staphylococcus aureus infections are growing problems worldwide with important implications in hospitals. The organism is normally present in the nasal vestibule of about 35% of apparently healthy individuals and its carriage varies between different ethnic and age groups. Staphylococcal nasal carriage among health workers is particularly important to establish new clones and track origin of infections during outbreak situations. To determine the carriage rate and compare the pulsed field gel patterns of the strains, nasal swabs were collected from 185 medical students in a teaching hospital in Lagos, Nigeria. Isolates of S. aureus were tested for heamolysin production, methicillin sensitivity and Pulsed Field Gel Electrophoresis (PFGE) was performed. The results showed S.aureus nasal carrier rate of 14% with significant rate among males compared to females. All the isolates produced heamolysin. Antibiotic susceptibility pattern revealed that majority of the isolates was susceptible. Five strains (19%) harboured resistant determinants to penicillin and tetracycline. None of the strains was resistant to methicillin. 44% of the isolates typed by PFGE had type B, the most predominant pulsotype. PFGE A clone exhibited a single resistance phenotype suggesting a strong clonal relationship that could punctual an outbreak in the hospital. The results speculate that nasal carriage among medical personnel could be a function of various risk factors. Personal hygiene and behaviour may however be the means to reducing colonization and spread of S.aureus in our hospitals.

Nasal Carriage Rate of Methicillin Resistant Staphylococcus aureus among Health Care Workers at a Tertiary Care Hospital in Kathmandu, Nepal

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Inducible clindamycin resistance and nasal carriage rates of<i> Staphylococcus aureus </i>among healthcare workers and community members

“…This finding is in-agreement with other studies 22,5 , which have been documented that the MRSA nasal carriage was higher among medical personnel than non-medical personnel. Yazgi et al (2003) 1 proposed that the colonization of the resistant strains rather than the frequency of S. aureus colonization is more important in the hospital personnel.…”

Staphylococcus epidermidis Prevails Staphylococcus aureus in Multispecies Biofilm under Gentamicin Stress

“…Whilst,Adesida et al [18] reported that 14.0% S. aureus nasal colonization in medical students in Lagos,Nigeria. Chopra et al [19] found that S. aureus comprised 31.11%; while CONS covered 13.33%.…”