Gram (+) cocci pose a global threat to human health due to the emergence of resistance to antibiotics. Linezolid has a broad spectrum of activity against a variety of pathogenic Gram (+) microorganisms, such as MRSA, VRS and VRE. However, the emergence of strains resistant to linezolid (LIN-R) and horizontal spread of resistance linked to the cfr gene, have been increasingly reported after approval of its clinical use. 

Although the prevalence of linezolid resistance remains low, the emergence of LIN-R strains is still a great concern. Today, linezolid sensitivity in Gram (+) clinical specimens is primarily monitored by surveillance programs in Europe and in the United States. Clinical isolates for surveillance of LIN-R strains include swabs from the nose (for screening of Staphylococcus), perianal and rectal areas (for screening of Enterococcus).