title: Living Conditions as a Driving Factor in Persistent Methicillin-resistant Staphylococcus aureus Colonization Among HIV-infected Youth.
abstract: Methicillin-resistant Staphylococcus aureus (MRSA) colonization has been linked to HIV-related sexual and social behaviors. MRSA risk factors may be different for HIV-infected children, adolescents and young adults. We investigated the association of MRSA colonization, persistent colonization and genotypes with potential risk factors among HIV-infected youth.
  
  
  
  For this case-control study, patients 24 years of age or younger attending 2 HIV reference centers were recruited from February to August 2012 and followed for 1 year. Nasal swabs were collected at enrollment and every 3 months. MRSA clones were characterized by staphylococcal chromosomal cassette mec typing, spa typing and multilocus sequence typing. We compared MRSA colonization and persistent colonization with patient demographic and clinical characteristics.
  
  
  
  Among 117 participants, MRSA colonization frequency (calculated for each collection based on the number of positive cultures per patient) was 12.8% at the first collection. The average MRSA colonization frequency was 10.4%. Our results showed 11.1% were persistent carriers (subjects with more than 1 positive culture in at least 3). Crowding was the only factor associated with MRSA colonization (P = 0.018). Persistent carriers had significantly higher (4.2 times) odds of living in a crowded household (95% confidence interval-1.1-16.2). We observed high genetic diversity among MRSA isolates, with t002/ST5 and t318/ST30 being the most frequent.
  
  
  
  MRSA colonization among HIV-infected youth is more closely related to living in a low-income or slum community than to HIV-related clinical factors. High genetic MRSA isolate diversity in our population suggests frequent transmission.
authors.affiliation: From the *School of Medicine, Graduate Program in Medical Science, Fluminense Federal University, Niterói, Rio de Janeiro, Brazil; †School of Public Health, University of California, Berkeley, Berkeley, California; ‡Laboratory of Molecular Epidemiology and Biotechnology, Rodolfo Albino University Laboratory, Rio de Janeiro, Brazil; §Graduate Program in Pathology, ¶Fluminense Federal University, Niterói, Rio de Janeiro, Brazil; ‖Department of Infectious Diseases, Servidores do Estado Federal Hospital; and **Institute of Mathematics and Statistics, Graduate Program in Medical Science, Rio de Janeiro, Brazil.
authors.forename: Maria Teresa C
authors.initials: MT
authors.lastname: Vieira
authors.forename: Mariel A
authors.initials: MA
authors.lastname: Marlow
authors.forename: Fábio
authors.initials: F
authors.lastname: Aguiar-Alves
authors.forename: Marcos Gabriel
authors.initials: MG
authors.lastname: Pinheiro
authors.forename: Maria de Fátima Nogueira de
authors.initials: Mde F
authors.lastname: Freitas Alves
authors.forename: Maria Letícia
authors.initials: ML
authors.lastname: Santos Cruz
authors.forename: Mariza Curto
authors.initials: MC
authors.lastname: Saavedra Gaspar
authors.forename: Rebeca
authors.initials: R
authors.lastname: Rocha
authors.forename: Luis Guillermo C
authors.initials: LG
authors.lastname: Velarde
authors.forename: Claudete A
authors.initials: CA
authors.lastname: Araújo Cardoso
mesh_terms: D000293:Adolescent; D002353:Carrier State / Q000453:epidemiology* / Q000382:microbiology; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D003441:Crowding; D005260:Female; D015658:HIV Infections / Q000150:complications*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D055624:Methicillin-Resistant Staphylococcus aureus; D009296:Nasal Cavity / Q000382:microbiology; D012111:Residence Characteristics; D012307:Risk Factors; D013203:Staphylococcal Infections / Q000150:complications* / Q000453:epidemiology* / Q000382:microbiology