Journal of Pharmaceutical and Allied Sciences JOPHAS INTRODUCTION It is now generally accepted that methicillin-resistant Staphylococcus aureus [MRSA] has proven to be one of the most widespread nosocomial pathogens of the late 20 th century [1]. The current observations the world over show that unlike a few years ago when only nosocomially acquired isolates were found to show very high incidence rates of resistant strains [2], community-acquired strains are now known to show enhanced resistance[s] to methicillin [3, 4]. • Correspondences Phone: 069-551-068, 0803-5890-195 E-mail: olonisteve@yahoo.com Journal of Pharmaceutical and Allied Sciences Volume 3 No 2 (2006) ISSN 1596-8499 Website: www.ajol.info/journals/jophas Methicillin-resistant organisms are of considerable clinical significance because they are frequently resistant to many other antibiotics as well as other anti-bacterial substances such as disinfectants, thereby causing infections that are quite difficult to treat or control [5]. World wide, many strains of S. aureus are already resistant to all antibiotics except Vancomycin [6], which has led to more frequent use of Vancomycin – the drug commonly relied on for treating MRSA infections [7]. Consequently, by 1996, the Center for Diseases Control and Prevention [USA] reported the first case of Vancomycin-intermediate S. aureus [i.e. S.aureus with Vancomycin MIC= 8-16 μg/ml], and later in 2002, S. aureus strains with high- level resistance to Vancomycin [MIC ≥ 32 μg /ml] were encountered [8]. Carriage of S. aureus in the nose is Journal of Pharmaceutical and Allied Sciences 3 (2) (2006) 365 - 370 NASAL CARRIAGE OF METHICILLI-RESISTANT STAPHYLOCOCCUS AUREUS WITH REDUCED VANCOMYCIN SUSCEPTIBILITY [MRSA-RVS] BY HEALTHY ADULTS IN ZARIA, NIGERIA. OLONITOLA, O.S. * 1 , OLAYINKA, B.O. 2 , SALAWU, M.J. 1 AND YAKUBU, S.E. 1 1. DEPARTMENT OF MICROBIOLOGY, AHMADU BELLO UNIVERSITY, ZARIA, NIGERIA. 2. DEPARTMENT OF PHARMACEUTICS AND PHARMACEUTICALMICROBIOLOGY, AHMADU BELLO UNIVERSITY, ZARIA, NIGERIA. ABSTRACT Staphylococcus aureus isolates were collected from anterior nares of fifty healthy adults in Zaria and their antibiotic susceptibility patterns determined. Seventy-two percent (72%) of the isolates were methicillin-resistant S. aureus, while 20% were methicillin- susceptible. The isolates were generally resistant to multiple antibiotics including chloramphenicol [78% resistance], penicillin [100% resistance], and tetracycline [66% resistance]. Vancomycin susceptibility studies revealed that 86% of the isolates were Vancomycin intermediate. There is a need to observe antibiotic use policies faithfully in order to prevent the spread of resistances. Key Words: Reduced-susceptibility, Staphylococcus aureus, Vancomycin, VISA.