July 2, 2015
Two epidemics of community-associated MRSA, both linked to the USA300 clone and its Latin American variant, appeared to derive from sister clades with a common ancestor, according to recent data.
Researchers collected 51 isolates of USA300 strains and the USA300 Latin American variant (USA300-LV) from parallel MRSA epidemics in South America and the United States. USA300-LV MRSA isolates were collected from a surveillance study conducted at tertiary care hospitals in Colombia, Ecuador and Venezuela between 2006 and 2007. Also identified for analysis were the first two strains of USA300-LV identified in South America in 2005. US300 strains were collected from several states between 1999 and 2012.