Nasal bacterial colonization in healthy people of the city of Santiago of Chile: Is there nasal carriage of community methicillin resistant Staphylococcus aureus?

Abstract

Introduction: Doesn’t exists agreement about normal nasal flora. Recently, it has emerged community-associated methicillin-resistant Staphylococcus aureus in people without known risk factors, producing a global health scare. Aim: Look for normal nasal flora and test the presence of MRSA-com. Material and method: Descriptive and prospective study, between October 2007 and October 2008, in healthy people. Was taken a sampling from nasal secretion, incubation and bacterial identification by conventional methods. Results: Studied population, average age 37.6±15.8 years, 55% female and 37.1% active smoking. We obtained 73% of positive cultures. We identified 18 bacterial species, the most common was Staphylococcus coagulase-negative (53%) and Staphylococcus aureus (22.7%). Was detected only one case of MRSA, and his genetic test was negative to prove community origin. Discusion: There is a high rate of nasal carriage of Staphylococcus coagulase- negative, like to that reported by international literature. Although the prevalence found for S aureus is the usual, there were no MRSA-com positive samples. This indicates that in Chile there is still no spread of clones of MRSA-com.