Nasal carriage of methicillin resistant Staphylococcus aureus among medical students of a private institution in Ilishan-Remo, Ogun State, Nigeria

*1Ajani, T. A., 1Elikwu C. J., 1Nwadike, V., 1Babatunde, T., 2Anaedobe, C. J., 1Shonekan, O., 1Okangba, C. C., 1Omeonu, A., 1Faluyi, B., 1Thompson, T. E., 1Ebeigbe, E., 3Eze, B. G., 4Ajani, M. A., 1Perelade, K., 1Amoran, M., 1Okisor, P., 1Worancha, T., 1Ayoade, J.,
1Agbeniga, E., 1Emmanuel, C., and 1Coker, C. A.

1Department of Medical Microbiology, Ben Carson School of Medicine/Babcock University Teaching Hospital, Ilishan-Remo, Ogun State, Nigeria

2Department of Medical Microbiology, University of Abuja, Federal Capital territory, Abuja, Nigeria

3Department of Histopathology, Babcock University Teaching Hospital, Ilishan-Remo, Ogun State, Nigeria

4Department of Histopathology, College of Medicine/University College Hospital, Ibadan, Oyo State, Nigeria *Correspondence to: solamustoo@yahoo.com; +2348034412609

Abstract:

Background: Nasal carriage of methicillin resistant Staphylococcus aureus (MRSA) is a major factor for its transmission especially from the health workers and medical students to their patients. There are a number of published data on the prevalence of MRSA among health workers but data on nasal colonization of medical students by MRSA are sparse in Nigeria. The objectives of this study are to determine the prevalence of nasal carriage of MRSA among medical students of the Ben Carson School of Medicine, Babcock University, Ilishan-Remo, Ogun State, Nigeria, and identify risk factors associated with this nasal carriage.

Methodology: A case control study involving 100 clinical (study group) and 100 pre- clinical (control group) medical students was undertaken between March 2018 and October 2019. Structured questionnaire was administered to obtain socio-demographic information and potential risk factors. Nasal swab was collected from each student and cultured for isolation of S. aureus by standard microbiology techniques. Phenotypic MRSA was detected by the cefoxitin 30μg disk diffusion method according to the guideline of Clinical and Laboratory Standards Institute. The mecA gene was detected by conventional polymerase chain reaction (PCR) assay.

Results: The prevalence of S. aureus nasal carriage among the study group was 14% (14/100) while the prevalence among the control group was 6% (6/100) (p=0.097). The prevalence of phenotypic MRSA among the study group was 4% (4/100) and 1% (1/100) among the control group (p=0.3687) while mecA gene was detected in 3 of the 4 (75%) phenotypic MRSA positive study participants and in the only (100%) phenotypic MRSA positive (1%) control group. Antibiotics usage without prescription, antibiotic treatment of common cold, and use of antibiotics in the previous one year, were significantly associated with MRSA carriage among the study group.

Conclusion: Although the prevalence of nasal carriage of S. aureus and MRSA among clinical and pre-clinical medical students was not statistically significant, the risk factors identified with carriage of MRSA among the study group indicates the need for antimicrobial stewardship program to reduce carriage and transmission of MRSA by medical students.

Keywords: methicillin resistant, Staphylococcus aureus, mecA gene, nasal carriage, medical students

Received March 25, 2020; Revised April 27, 2020; Accepted April 28, 2020 Copyright 2020 AJCEM Open Access. This article is licensed and distributed under the terms of the Creative Commons Attrition 4.0 International License <a rel=”license” href=”//creativecommons.org/licenses/by/4.0/”, which permits unrestricted use, distribution and reproduction in any medium, provided credit is given to the original author(s) and the source.

Continue reading “Nasal carriage of methicillin resistant Staphylococcus aureus among medical students of a private institution in Ilishan-Remo, Ogun State, Nigeria”

Non detection of mecA gene in methicillin resistant Staphylococcus aureus isolates from pigs

C.N. Nwaogaraku, S.I. Smith, J.A. Badaki

 

Abstract

Background: Methicillin resistant Staphylococcus aureus (MRSA) have become a global health problem causing infections in both humans and livestock, ranging from skin and soft tissue to life threatening blood stream infections. The mecA gene is known to confer resistance to MRSA isolates. This study investigated the carriage of mecA gene by MRSA isolates from pigs.

Methods: One hundred non duplicate staphylococcal isolates recovered from blood samples of pigs in Bariga district of Lagos State at the Molecular Biology and Biotechnology unit of the Nigerian Institute of Medical Research were used in the study. S. aureus was identified by cultural characteristics, and positive catalase, coagulase and deoxyribonuclease tests. Phenotypic methicillin resistance was determined by the modified Kirby Bauer disk diffusion method and mecA gene was detected by conventional polymerase chain reaction (PCR) assay.

Results: Twenty-five S. aureus were identified, of which 11 (44%) were MRSA by phenotypic method. All the isolates were mecA negative on PCR.

Conclusion: The MRSA phenotype observed in the pig isolates in this study appears not to be the classical mecA mediated resistance. There may be alternative mechanisms of resistance in MRSA isolates in pigs.

Keywords: MRSA, phenotypic, mecA gene, PCR, pigs

Download full journal in PDF below

Non detection of mecA gene in methicillin resistant Staphylococcus aureus isolates from pigs