Feasibility of a preventive HIV-1 vaccine cohort among persons attending sexually transmitted disease clinics in Thailand.
Persons attending sexually transmitted disease clinics at three sites in Thailand were recruited to participate in a 1-year study of HIV-1 incidence. Between September 1995 and February 1996, 31% (371 of 1205) of eligible men and 24% (161 of 659) of eligible women agreed to participate. At enrollment, HIV-1 seropositivity was 3.8% among men and 2.5% among women. Follow-up of the 514 participants who were seronegative at baseline was 78% at the 12-month visit. During the study period, 53% of men reported 2 or more sexual partners, 31% reported sex with a commercial sex worker (CSW), and 33% with a casual partner. Of those visiting CSWs, 72% reported consistent condom use. Among women, 11% reported 2 or more sexual partners. Decreased HIV risk behaviors among men were observed during the study. Four incident infections occurred in men (1.4/100 person-years, 95% confidence interval [CI] = 0.4-3.6) and none among women. Based on the observed HIV-1 incidence, HIV vaccine efficacy trials in such populations would have to be larger than previously planned or more selective of high risk subgroups for recruitment.
Markowitz
L E
LE
Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand. lem2@cdc.gov
Sirisopana
N
N
Charonwatanachokchai
A
A
Julvanichpong
W
W
Siraprapasiri
T
T
Palanuvej
T
T
Siriwongrangsun
P
P
Tungsakul
V
V
Pumratana
K
K
Chitwarakorn
A
A
Michael
R A
RA
Brown
A E
AE
D016915:AIDS Vaccines; D000328:Adult; D005260:Female; D005500:Follow-Up Studies; D015658:HIV Infections / Q000453:epidemiology / Q000517:prevention & control*; D015497:HIV-1; D006801:Humans; D008297:Male; D015995:Prevalence; D011446:Prospective Studies; D012309:Risk-Taking; D012749:Sexually Transmitted Diseases; D013785:Thailand / Q000453:epidemiology
D016915:AIDS Vaccines