A Prospective Study of Sexual Transmission of Human T Lymphotropic Virus (HTLV)–I and HTLV-II

• Published in: The Journal of infectious diseases Vol. 191; no. 9; pp. 1490 - 1497
• Main Authors: Roucoux, Diana F., Wang, Baoguang, Smith, Donna, Nass, Catharie C., Smith, James, Hutching, Sheila T., Newman, Bruce, Lee, Tzong-Hae, Chafets, Daniel M.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Chicago, IL The University of Chicago Press 01.05.2005; University of Chicago Press; Oxford University Press
• Subjects: Adult; Aged; Biological and medical sciences; Blood; Blood donation; Cohort Studies; Condoms; Cross-Sectional Studies; Female; Fundamental and applied biological sciences. Psychology; HTLV-I Infections - epidemiology; HTLV-I Infections - transmission; HTLV-II Infections - epidemiology; HTLV-II Infections - transmission; Human T lymphotropic virus 1; Human T lymphotropic virus 2; Humans; Incidence; Infections; Infectious diseases; Male; Medical sciences; Microbiology; Middle Aged; Miscellaneous; Predisposing factors; Risk Factors; Sexual transmission; Sexually transmitted diseases; Sexually Transmitted Diseases - epidemiology; Sexually Transmitted Diseases - transmission; Sexually Transmitted Diseases - virology; Socioeconomic Factors; United States - epidemiology; Virology; Viruses; United States; Virus; Infection; HTLV-II virus; Sexually transmitted disease; Deltaretrovirus; Microbiology; Retroviridae; HTLV-I virus
• ISSN: 0022-1899; 1537-6613
• DOI: 10.1086/429410

BackgroundCross-sectional studies support sexual transmission of human T lymphotropic virus (HTLV)–I/II; however, prospective incidence data, particularly for HTLV-II, are limited MethodsA cohort of 85 HTLV-positive (30 with HTLV-I and 55 with HTLV-II) blood donors and their stable (⩾6 months) heterosexual sex partners were followed biannually over the course of a 10-year period ResultsFour of 85 initially seronegative sex partners of HTLV-I and -II carriers seroconverted, for an incidence rate (IR) of 0.6 transmissions/100 person-years (py) (95% confidence interval [CI], 0.2–1.6). This includes 2 HTLV-I transmissions/219 py (IR, 0.9 transmissions/100 py [95% CI, 0.1–3.3]) and 2 HTLV-II transmissions/411 py (IR, 0.5 transmissions/100 py [95% CI, 0.06–1.8]), with no significant difference by HTLV type. There were 2 male-to-female (IR, 1.2 transmissions/100 py [95% CI, 0.1–4.3]) and 2 female-to-male (IR, 0.4 transmissions/100 py [95% CI, 0.05–1.6) transmissions. HTLV-I or -II proviral load was 2 log10 lower in newly infected partners than in index positive partners who transmitted HTLV (P=.007) ConclusionsThe incidence of sexual transmission of HTLV-II may be similar to that of HTLV-I, and female-to-male transmission may play a more important role than previously thought. HTLV-I and -II proviral load may be lower in sexually acquired infection, because of a small infectious dose