Online Program

Seroprevalence and demographic determinants of human t-lymphotropic virus type-1 and -2 infections among first-time blood donors, u.s. 2000-2009

Monday, November 4, 2013

Yun Brenda Chang, MPH, Department of Biostatistics, Columbia University, New York, NY
Edward Murphy Jr., MD, MPH, Blood Systems Research Institute, San Francisco, CA
Zhanna Kaidarova, MBA, Blood Systems Research Institute, San Francisco, CA
Daniel Hindes, Blood Systems Research Institute, San Francisco, CA
Marjorie Bravo, MD, Blood Systems Inc., Scottsdale, AZ
Nancy Kiely, Blood Systems Inc., Scottsdale, AZ
Hany Kamel, MD, Blood Systems Inc., Scottsdale, AZ
Denise Dubay, Blood Systems Inc., Scottsdale, AZ
Barbara Hoose, NP, Blood Systems Inc., Scottsdale, AZ
Objectives. We determined the seroprevalence of human T-lymphotropic virus types 1 and 2 (HTLV-1 and –2), which has not been estimated in the United States since 2001. Methods. Data on all first-time blood donors in a large network of United States blood centers was examined during the period 2000-2009. HTLV-1 and -2 antibody was measured by enzyme immunoassay (EIA) screening and repeatedly reactive samples were confirmed with immunofluorescence assay or recombinant immunoblot. Prevalence rates were calculated, and odds ratios (OR) and 95% confidence intervals (CI) for associations with demographic characteristics were assessed using multivariable logistic regression. Results. Among 2,047,740 first-time donors, 104 donors were seropositive for HTLV-I infection (prevalence 5.1 (95% CI: 4.1 - 6.1) per 100,000) and 300 donors were seropositive for HTLV-2 infection (prevalence 14.7 (95% CI 13.0 - 16.3) per 100,000). Prevalence was lower than reported in the 1990's but stable from 2000 to 2009. HTLV-1 infection was associated with female sex (OR = 1.56, 95% CI 1.05-2.32), older age, and Black and Asian race/ethnicity, whereas HTLV-2 infection was associated with female sex (OR = 2.13, 95% CI 1.67-2.73), older age, Black, Hispanic and Other race/ethnicity , Western (OR=4.12, 95% CI 2.16-7.82) and Southwestern (OR=2.47, 95% CI 1.28-4.78; both vs. Northern) regions, and lower educational level. Conclusions. HTLV-1 and -2 prevalence has stabilized in United States blood donors since the turn of the century. Higher prevalence of HTLV-2 in the West and Southwest may be attributed to localization of injection drug use or endemic Amerindians.

Learning Areas:

Conduct evaluation related to programs, research, and other areas of practice
Implementation of health education strategies, interventions and programs
Public health or related research

Learning Objectives:
Name the routes of transmission for the Human T-lymphotropic virus (HTLV). Describe global prevalence rates of HTLV. Explain the change in demographic determinants of a rare virus at the national level in the U.S. Compare current prevalence of HTLV 1 and 2 virus to past prevalence from 20 years ago. Identify the demographic determinants and risk factors of population subgroups for being seropositive for HTLV virus. Differentiate the geographic determinants of HTLV and the difference in routes of transmission among populations.

Keyword(s): Epidemiology, Public Health

Presenting author's disclosure statement:

Qualified on the content I am responsible for because: I analyzed the data and wrote the manuscript for future publication as a epidemiology intern at the Blood Systems Research Institute, and worked on the project for my masters thesis.
Any relevant financial relationships? No

I agree to comply with the American Public Health Association Conflict of Interest and Commercial Support Guidelines, and to disclose to the participants any off-label or experimental uses of a commercial product or service discussed in my presentation.