Methicillin-resistant Staphylococcus aureus (MRSA) infections are an important cause of morbidity, especially among human immunodeficiency virus (HIV)-infected persons. Since an increasing number of MRSA skin and soft tissue infections involve the perigenital areas, some have suggested that these infections may be sexually transmitted. We performed a cross-sectional study among HIV-infected adults from 4 geographically diverse United States military HIV clinics to determine the prevalence of and the factors (including sexual practices) associated with MRSA colonization. Swabs were collected from the nares, throat, axillae, groin area, and perirectal area for S. aureus colonization. Data on sociodemographic characteristics, medical conditions, and sexual history were collected. Multivariate logistic regression models evaluated factors associated with carriage. We studied 550 HIV-infected adults with a median age of 42 years; 93% were male; and race/ethnicity was white for 46%, African American for 35%, and other for 19%. Median CD4 count was 529 cells/mm3, 11% had a history of a MRSA infection, and 21% had a sexually transmitted infection within the last year, including 8% with syphilis. One hundred eighty (33%) were colonized with S. aureus and 22 (4%) with MRSA. The most common location for carriage was the nares, followed by the perigenital area (groin or perirectal area). Factors associated with MRSA carriage in the multivariate analyses included a sexually transmitted infection in the last year (odds ratio [OR], 4.2; p < 0.01), history of MRSA infection (OR, 9.4; p < 0.01), and African American compared with white race/ethnicity (OR, 3.5; p = 0.01). In separate multivariate models, syphilis, nongonococcal urethritis, and public bath use were also associated with MRSA carriage (all p < 0.01). In conclusion, a history of recent sexually transmitted infections, including syphilis and urethritis, was associated with MRSA carriage. These data suggest that high-risk sexual activities may play a role in MRSA transmission.
Abbreviations: ACME = arginine catabolic mobile element, AIDS= acquired immunodeficiency syndrome, CI = confidence interval, HAART = highly active antiretroviral therapy, HIV = human immunodeficiency virus, HSV2 = herpes simplex type 2, IQR = interquartile range, MRSA = methicillin-resistant Staphylococcus aureus, MSM = menwho have sex with men, MSSA = methicillin-sensitive Staphylococcus aureus, NGU = nongonococcal urethritis, NMCP = Naval Medical Center Portsmouth, NMCSD = Naval Medical Center of San Diego, OR = odds ratio, PVL = Panton-Valentine leukocidin, SAMMC = San Antonio Military Medical Center, SSTIs = skin and soft tissue infections, STI = sexually transmitted infection, TMP-SMX = trimethoprim-sulfamethoxazole, WRAMC = Walter Reed Army Medical Center.
From Infectious Disease Clinical Research Program (NFCC, AW, DRH, TL, GC, AM, KM, BKA), Uniformed Services University of the Health Sciences, Bethesda, Maryland; Infectious Disease Clinic (NFCC, AM), Naval Medical Center San Diego, San Diego, California; San Diego State University (NFCC, AHS, SKB), San Diego, California; Infectious Disease Clinic (AW), Walter Reed Army Medical Center, Washington, DC; Infectious Disease Service (DRH, KM), San Antonio Military Medical Center, San Antonio, Texas; Infectious Disease Clinic (TL), Naval Medical Center Portsmouth, Virginia; and Division of Biostatistics (GC), University of Minnesota, Minneapolis, Minnesota.
*The members of the Infectious Disease Clinical Research Program HIV Working Group are listed in Appendix A.
Support for this work (IDCRP-003) was provided by the Infectious Disease Clinical Research Program (IDCRP), a Department of Defense program executed through the Uniformed Services University of the Health Sciences and by the Global Emerging Infections Surveillance and Response System (GEIS), a division of the Armed Forces Health Surveillance Center. This project has been funded in whole, or in part, with federal funds from the National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), under Inter-Agency Agreement Y1-AI-5072.
The USA type reference strains used for pulse-field gel electrophoresis (PFGE) analysis were obtained through the Network on Antimicrobial Resistance in Staphylococcus aureus (NARSA) program supported under NIAID/NIH Contract No. HHSN272200700055C.
Conflict of interest: The authors from the IDCRP have no financial interest in this work. All authors contributed to the content of the manuscript and concurred with the decision to submit it for publication.
The content and views expressed in this publication are the sole responsibility of the authors and do not necessarily reflect the views or policies of the NIH or the Department of Health and Human Services, the Department of Defense, or the Departments of the Army, Navy, Air Force, or the United States government. Mention of trade names, commercial products, or organizations does not imply endorsement by the United States government.
Some of these data were presented at the 5th IAS Conference on HIV Pathogenesis, Treatment and Prevention, Cape Town, South Africa, July 19-22, 2009, and at the 49th Annual Meeting of the Infectious Diseases Society of America, Boston, MA, October 20-23, 2011.
Reprints: Dr. Nancy F. Crum-Cianflone, c/o Clinical Investigation Department (KCA), Naval Medical Center San Diego, 34800 Bob Wilson Drive, Suite 5, San Diego, CA 92134-1005 (e-mail: firstname.lastname@example.org).