From 2005 through 2007, Seattle health care providers identified cases of primary multiclass drug-resistant (MDR) HIV-1 with common patterns of resistance to antiretrovirals (ARVs). Through surveillance activities and genetic analysis, the local Health Department and the University of Washington identified phylogenetically linked cases among ARV treatment-naive and -experienced individuals.
HIV-1 pol nucleotide consensus sequences submitted to the University of Washington Clinical Virology Laboratory were assessed for phylogenetically related MDR HIV. Demographic and clinical data collected included HIV diagnosis date, ARV history, and laboratory results.
Seven ARV-naive men had phylogenetically linked MDR strains with resistance to most ARVs; these were linked to 2 ARV-experienced men. All 9 men reported methamphetamine use and multiple anonymous male partners. Primary transmissions were diagnosed for more than a 2-year period, 2005-2007. Three, including the 2 ARV-experienced men, were prescribed ARVs.
This cluster of 9 men with phylogenetically related highly drug-resistant MDR HIV strains and common risk factors but without reported direct epidemiologic links may have important implications to public health. This cluster demonstrates the importance of primary resistance testing and of collaboration between the public and private medical community in identifying MDR outbreaks. Public health interventions and surveillance are needed to reduce transmission of MDR HIV-1.
From the *HIV/AIDS Epidemiology Unit, HIV/AIDS Program, Public Health-Seattle & King County, Seattle, WA; †Departments of Epidemiology, Laboratory Medicine, Pediatrics, Allergy and Infectious Diseases, Family Medicine, Medicine, and Health Services, University of Washington, Seattle, WA; ‡Department of Childhood Infection, Seattle Children's Hospital Research Institute, Seattle, WA; §Virginia Mason Medical Center, Seattle, WA; ‖Country Doctor Community Clinic, Seattle, WA; and ¶Department of HIV Research, Swedish Medical Center, Seattle, WA.
Received for publication March 1, 2008; July 2, 2008.
Supported in part by a Cooperative Agreement with the US Centers for Disease Control and Prevention.
Portions of this work have been presented at the International Society of Sexually Transmitted Disease Research meeting, July 29, 2007, to August 1, 2007, Seattle, WA.
The authors report no conflicts of interest.
Correspondence to: Susan E. Buskin, PhD, MPH, Senior Epidemiologist, Public Health-Seattle & King County, 400 Yesler Way, 3rd Floor, Seattle, WA 98104 (e-mail: email@example.com).