Background. Genetic variation in human immunodeficiency virus (HIV)-1 poses significant public-health and clinical challenges. In North America, subtype B is most prevalent. HIV-1 subtyping is not integrated into routine HIV/acquired immunodeficiency syndrome surveillance in the United States. In 2003, the Minnesota Department of Health piloted HIV-1 subtyping with routine surveillance to describe the existence and variety of non-subtype B strains. Methods. Targeted HIV-1 subtype surveillance was conducted on 98 African-born HIV-infected patients. Sentinel subtype surveillance was conducted in a Minneapolis sexually transmitted disease clinic on 28 newly diagnosed non-African HIV-positive patients. Subtype determination was based on a partial sequence of the gp41 region of the HIV-1 env gene. Results. Subtyping was successful for 87 of 98 samples from African-born HIV-infected patients; 95% were non-B subtypes. The 7 subtypes observed were consistent with strains endemic in patients' birth regions. Subtyping was also completed for samples from 25 of 28 non-African-born patients; all were subtype B. Conclusions. Multiple HIV-1 subtypes are present in Minnesota. Our data suggest that most of the HIV cases in Minnesota among African-born patients are non-B subtypes. Population-based surveillance inclusive of groups at high risk for variant strains is needed to monitor the prevalence and variety of HIV subtypes in the United States.
Bibliographical noteFunding Information:
Received 24 September 2004; accepted 28 December 2004; electronically published 27 May 2005. Presented in part: XV International AIDS Conference, 11–16 July 2004, Bangkok, Thailand (abstract MoPeC3427). Financial support: US Centers for Disease Control and Prevention (cooperative agreement U62/CCU523560-02 for HIV/AIDS surveillance). Reprints or correspondence: Dr. Tracy Sides, Minnesota Dept. of Health, PO Box 9441, Minneapolis, MN 55414-9441 (firstname.lastname@example.org).