Sexually Transmitted Diseases Among Persons With HIV With Low Viral Load

Abstract

To the Editors HIV transmission is rare at viral loads (VL) up to several thousand copies.1 However, persons with low VL are at risk for sexually transmitted disease (STD) if they engage in unprotected sex, which may be related to beliefs about lower HIV infectiousness.2 Among persons with HIV, coinfection with another STD is common3 but has not been studied in a population-based group that is generally assumed unlikely to transmit HIV.4 We investigated STD prevalence among persons with different HIV VL levels, focusing on the subpopulation with low VL, by matching HIV and STD registry data. The New York City (NYC) HIV/AIDS surveillance registry contains data on New Yorkers diagnosed as having AIDS since 1981 and HIV infection or disease since 2000. Since 2005, it has received HIV-related laboratory results on persons living with HIV/AIDS (PLWHA) in NYC. The NYC STD surveillance registry contains data on New Yorkers diagnosed and reported to have any of 7 notifiable STD. A cross-registry match included 138,235 PLWHA as of March 30, 2011, excluding persons who died before January 1, 2000, and STD cases diagnosed January 1, 2000 to June 30, 2010. Viral load test dates and results were obtained from the HIV registry as of June 30, 2011. Among 69,418 PLWHA in 2009 who had 1 or more VL tests in 2009 and survived 31 days or longer after VL measurement (62.8% of all 2009 PLWHA), we calculated the proportion of those with a diagnosis of early syphilis, gonorrhea, chlamydia, or lymphogranuloma venereum within 31 days before or after the last VL in 2009 and characterized demographic and clinical characteristics and coinfection rates of PLWHA whose last VL was low (defined as 0–3499 copies/mL).1 Last VL was 0 to 3499 for 55,558 persons, 80.0% of PLWHA in the analysis, among whom last VL was less than 1000 copies/mL for 92.9% and less than 400 copies/mL for 87.3%. Of the 55,558, 478 (0.9%) had an STD diagnosis within 31 days of their low VL, with the highest prevalence among persons aged 20 to 29 years (3.1%) and 30 to 39 years (1.9%) and men who have sex with men (MSM; 1.8%) (Table 1). Early syphilis (43.1%) and chlamydia (36.3%) were the most frequent STD among PLWHA with low VL, followed by gonorrhea (19.7%) and lymphogranuloma venereum (0.8%). Most persons with STD and low VL were male (91.4%) and, specifically, MSM (73.8%). Sexually transmitted disease prevalence was higher among PLWHA with higher last VL (1.9% among 3500–9999; 2.0% among 10,000–99,999; and 2.2% among ≥100,000 [P trend <0.0001]).TABLE 1: STD Diagnosis Within 31 Days Among PLWHA With a Low (<3500) VL, by Demographics, Transmission Risk, and Clinical Characteristics, for All Persons and MSM, NYC 2009Overall, bacterial STD was rare (<1%) among PLWHA who, on the basis of their low VL, are assumed unlikely to transmit HIV. Still, these STD prevalence data suggest ongoing risk behavior (unprotected sex) among some persons with low VL and reinforce the value of STD screening and risk reduction services, even for persons with low HIV VL. Subgroups such as young adults and MSM had a higher STD prevalence that would be even higher if the highly prevalent genital herpes simplex virus were reportable also. Previous studies have found disproportionate STD rates among MSM PLWHA locally5,6 and nationally,7 and a recent mathematical model suggested that increased unprotected sex among MSM has diminished the population-level benefits of antiretroviral treatment for HIV prevention.8 Our findings reinforce the value of STD screening and risk reduction counseling among persons with low HIV VL. Ellen W. Wiewel, MHS Sarah L. Braunstein, PhD, MPH Preeti Pathela, DrPH, MPH Qiang Xia, MD, MPH Lucia V. Torian, PhD New York City Department of Health and Mental Hygiene New York, NY