Open Access Peer-reviewed

Epidemiology of Vancomycin Resistant Staphyloccus Aureus among Clinical Isolates in a Tertiary Hospital in Abakaliki, Nigeria

Alo Moses1, Ugah Uchenna2,, Okoro Nworie1

1Department of Biological Science, Federal University Ndufu-Alike Ikwo, Ebonyi State

2Department of Medical Laboratory Science, Ebonyi State University Abakaliki, Ebonyi State

American Journal of Epidemiology and Infectious Disease. 2013, 1(3), 24-26. DOI: 10.12691/ajeid-1-3-2
Published online: August 25, 2017


Staphylococcus aureus is a successful pathogen due to a combination of numerous bacteria immune-evasive strategies. The increased incidence of MRSA has led to more frequent use of vancomycin, the drug commonly relied upon as last resorts for treating MRSA infections. As a consequence, selective pressure was established that led to the emergence of strains of S. aureus and other species of Staphylococci with decreased susceptibility to vancomycin and other glycopeptides. The aim of our study was to determine the prevalence of vancomycin resistant S. aureus among clinical isolates in a tertiary health care facility in Abakaliki metropolis, the capital of Ebonyi State, South Eastern Nigeria. The susceptibility of S. aureus strains to vancomycin was determined by Kirby-Bauer disk diffusion technique as well as by tube dilution method. Among the 355 S. aureus isolates tested, 272 (76.6%) isolates were susceptible (zone diameter ≥ 15mm, MIC 0.5-2μg/ml) 64 (18.0%) isolates were intermediate (zone diameter ≤ 14mm, MIC 4-8μg/ml) while 19 (5.4%) isolates were resistant (zone diameter ≤ 14mm, MIC ≥ 16μg/ml). When subjected to statistical analysis, this prevalence rate was statistically non-significant (p < 0.05). But, nevertheless, clinically relevant considering the overall implication in the transfer of resistant gene.


vancomycin, resistance, Staphylococcus aureus, Abakaliki
[1]  Tiwari H.K and Sen M.R. Emergence of vancomycin resistant Staphylococcus aureus (VRSA) from a tertiary hospital from northern part of india. BMC Infectious Diseases. 6:156-161. October, 2006.View Article  PubMed
[2]  Lowy F.D Staphylococcus aureus infections. New England Journal of Medicine. 339:520-532. 1998.View Article  PubMed
[3]  Greenwood D., Slack, RCB., Peatherer JF (ed). Medical Microbiology. 15th ed. ELST- Churchill Livingstone. P168-174. 1995.
[4]  Brumfil W and Hamilton-Miller J. methicillin resistant Staphylococcus aureus. New England Journal of Medicine. 320:1188-1196. 1989.View Article  PubMed
[5]  Chambers H.F. methicillin resistance in Staphylococci: molecular and biochemical basis and clinical implications. Clinical Microbiology Reviews. 10: 781-791. 1997. PubMed
[6]  Whitener C.J., Park S.Y., Browne F.A., Parent L.J., Julian K., Bozdogan B., Apeelbaum P.C., Chaitram J., Weigel L.M., Jernigan J., McDougal L.K., Tenover F.C. and Fridkin S.K. Vancomycin – resistant Staphylococcus aureus in the absence of vancomycin exposure. Clinical Infectious Diseases. 38:1049-1055. 2004.View Article  PubMed
[7]  Tenover F.C., Biddle J.W., Lancaster M.V. Increasing resistance to vancomycin and other glycopeptides in Staphylococcus aureus. Emerging Infectious Diseases. 7:327-332. 2001.View Article  PubMed
[8]  Hiramatsu K., Hanaki H., Ino T., Yabuta K., Oguri T., Tenover F.C. methicillin resistant Staphylococcus aureus clinical strain with reduced vancomycin susceptibility. Journal of Antimicrobial Chemotherapy. 40: 135-136. 1997View Article  PubMed
[9]  Centers for Disease Control and Prevention. Staphylococcus aureus resistant to vancomycin – United States, 2002. Morbidity and Mortality Weekly Report MMWR. 51:565-567. 2002.
[10]  National Committee for Clinical Laboratory Standards. Performance Standards for Antimicrobial susceptibility testing; 15th informational supplement M100-S15. National Committee for Clinical Laboratory Standards. Wayne, PA. 2007
[11]  National Committee for Clinical Laboratory Standards. Methods for antimicrobial susceptibility tests for bacteria that grow aerobically. 5th ed. Approved standard, M7-A5. National Committee for Clinical Laboratory Standards. Wayne, PA. 2007
[12]  Clinical and Laboratory Standards Institute. Performance Standards for Antimicrobial Susceptibility Testing; Seventeenth Informational Supplement. M100-S17. Volume 27(1): 1-77. Clinical and Laboratory Standards Institute. Wayne, PA. January, 2007.
[13]  Hiramatsu K. vancomycin – resistant Staphylococcus aureus: a new model of antibiotic resistance. The Lancet infectious Diseases. 1:147-155. 2001.View Article
[14]  Tenover F.C., Lancaster M.V., Hill B.C. Characterization of staphylococci with reduced susceptibility to vancomycin and other glycopeptides. Journal of Clinical Microbiology. 36: 1020-1027. 1998. PubMed
[15]  Ploy M.C, Grelaud C., Martin C., de Lumley L., Denis F. First clinical isolate of vancomycin – intermediate Staphylococcus aureus in a French hospital. Lancet 251:1212. 1998.View Article
[16]  Kim M-N., Pai CH., Woo J.H., Ryu J.S., Hiramatsu K. Vancomycin – intermediate Staphylococcus aureus in Korea. Journal of Clinical Microbiology. 38: 3879-3881. 1998.
[17]  Ferraz V., Duse A.G., Kassel M., Black A.D., Ito T., Hiramatsu K. Vancomycin – resistant Staphylococcus aureus occurs in South Africa. South African Medical Journal. 90: 1113. 2000. PubMed