The Center for Disease Dynamics, Economics & Policy

Resistance to multiple drugs is steadily declining

BACKGROUND

Coagulase-negative staphylococci (CoNS) are a broad group of species that commensally inhabit the human skin, mucous membranes (S. hominis, S. epidermidis), and vaginal tract (S. saprophyticus). Although they are less virulent than the coagulase-positive S. aureus and almost never pathogenic in healthy individuals, their persistence on hospital surfaces and devices has made them the most common source of bloodstream infections. Overlooked in the past because they primarily contaminated cultures, CoNS have emerged as a clinically relevant pathogen implicated in up to 30%of health care–associated sepsis.

Although there is an encouraging downward trend in multidrug resistance, more than 10% of CoNS infections fail to respond to multiple drugs in vitro and may require vancomycin. Use of this drug of last resort is worrisome because it may contribute to the development of resistance among S. aureus, giving rise to vancomycin resistance in that organism and creating a new superbug, known as VRSA. 

RESISTANCE BY U.S. CENSUS DIVISION, 1999-2010