[1] Univ Fed Rio Grande do Sul, Med Sci Postgrad Program, BR-90000000 Porto Alegre, RS, Brazil
[2] Hosp Clin Porto Alegre, Hosp Infect Control Comm, Porto Alegre, RS, Brazil
[3] Ctr Univ IPA Metodista, Porto Alegre, RS, Brazil
[4] Hosp Clin Porto Alegre, Microbiol & Mol Biol Unit, Porto Alegre, RS, Brazil