Monitoring changes in adolescent sexual risk behaviors and sexually transmitted infections is critical for evaluating the effectiveness of human immunodeficiency virus and other prevention programs, but population-based data on adolescents in Thailand are limited. We report findings from 2 cross-sectional surveys conducted in 1999 and 2002 among 15-to 21-year-old vocational students.
In 1999 and 2002, 1725 and 966 students, respectively, were interviewed using computer-assisted self-interview methods. Urine samples were collected and tested for Chlamydia trachomatis and Neisseria gonorrhoeae by polymerase chain reaction.
From 1999 to 2002 C. trachomatis prevalence increased from 3.2% to 7.5% (P <0.001) in women and from 2.5% to 6.0% (P <0.001) in men. There was an increase in the reported mean lifetime number of steady sexual partners among both men (3.4–4.7, P = 0.01) and women (2.5–3.3, P <0.001), and in the mean lifetime number of casual partners among men (1.1–2.1, P <0.001) and women (0.3–1.1, P = 0.04). Reported consistent condom use decreased significantly among women with casual partners (43%–19%, P = 0.03) but not among men (25%–31%, P = 0.31).
Our study identified important increases in the prevalence of chlamydial infection and in sexual risk behaviors among Thai adolescents over a 3-year period. These findings are consistent with other studies suggesting profound social changes are changing norms of adolescent sexual behavior in Thailand, and highlight the need for adolescent sexual health services and prevention programming.
Two studies of adolescent sexual risk behaviors and biomarkers in northern Thailand found that both risk behaviors and Chlamydia prevalence increased over a 3-year period.
From the *Thailand Ministry of Public Health, US Centers for Disease Control and Prevention Collaboration, Nonthaburi, Thailand; †US Centers for Disease Control and Prevention, Atlanta; and ‡Chiang Rai Hospital, Chiang Rai, Thailand
Supported by the US Centers for Disease Control and Prevention.
Disclaimer: The findings and conclusions in this article are those of the authors and do not necessarily represent the views of the US Centers for Disease Control and Prevention.
Correspondence: Sara J. Whitehead, MD, MPH, Thailand MOPH—US CDC Collaboration, P.O. Box 139, Nonthaburi 11000, Thailand. E-mail: firstname.lastname@example.org.
Received for publication November 29, 2007, and accepted April 11, 2008.