Screening of nasal carriage for Staphylococcus aureus and their resistance
to oxacillin and cefoxitin among medical students in Karbala University
Introduction
Staphylococcus aureus has long been recognized as an
important human pathogen.1 The anterior nares represent
the primary ecological reservoir of S. aureus in humans, and
nasal carriage is a major risk factor for a variety of infections.2
Three patterns of nasal carriages are known (persistent
carrier, intermittent, and non-carrier). Approximately 20%
of the individuals almost always carry one type of strain and
they are called persistent carriers. A large proportion of the
population (60%) harbours S. aureus intermittently, and the
strains change with varying frequencies. Such persons are
called intermittent carriers. Finally, a minority of the people
(20%) almost never carry S. aureus and they are called noncarriers.
A persistent carriage is more common in children
than in adults, and many people change their pattern of
carriage between the age of 10 and 20 years. The reasons for
these differences in the colonization patterns are unknown.3
Healthcare workers (HCWs) constitute an important
reservoir of S. aureus. Several studies have reported that the
rate of the nasal carriage of S. aureus among the HCWs
ranges from 16.8% to 56.1%.4–7
