Methicillin Resistance in Staphylococcus aureus: a Review of the Molecular Epidemiology; Clinical Significance and Laboratory Detection Methods

ABSTRACT

BACKGROUND: Despite the volume of knowledge; enhanced surveillance and infection control measures adopted by health care institutions to address the endemicity and frequent disease outbreaks by methicillin-resistant Staphylococcus aureus (MRSA) in hospitals and health care facilities worldwide; infections due to this organism are still responsible for about 50of hospital acquired S. aureus infections; with increasing morbidity and mortality. OBJECTIVE: To provide regional clinicians with current information on the molecular epidemiology; laboratory detection and clinical aspects of MRSA. METHODS: A review of published literatures on MRSA in Medical Libraries and bibliographic citations on PubMed; Medline and Africa Index Medicus on molecular epidemiology and clinical diseases caused by MRSA and the assessment of the recent laboratory diagnostic approaches. RESULTS: This review showed that there has been intercontinental spread of some highly pathogenic clones of MRSA threatening to create public health hazard of unprecedented proportion; with the greatest challenge to mankind; being the development of resistance to multiple antibiotics; which in recent times had included resistance to vancomycin and other glycopeptides; the only antibiotic group effective against it. Added to this burden is the emergence of more virulent strains of community-associated MRSA (CAMRSA) which at the turn of the century; has been increasingly reported to cause infections and outbreaks in populations without predisposing risk factors; with attendant high morbidity and mortality. CONCLUSION: There is need for active MRSA surveillance by healthcare institutions in Africa to identify potential outbreaks; and vigilance in the enforcement of infection control measures such as rational prescription of antibiotics; handwashing; disinfection and sterilization that can limit the emergence and spread of more resistant clones of MRSA