Improving second-generation surveillance: the biological measure of unprotected intercourse using prostate-specific antigen in vaginal secretions of West African women.
BACKGROUND
Second-generation surveillance for HIV includes measures of high-risk behaviors among the general adult population and sex workers (SW). Questionnaires are prone to social desirability biases because individuals minimize the frequency of behaviors not expected from them.


OBJECTIVE
Determine whether the prostate-specific antigen (PSA) could be used as a biological marker of unprotected intercourse.


METHODS
We measured the presence of PSA in vaginal secretions of women who were (n = 508) or were not (n = 658) SW presenting with vaginal discharge in health facilities of Ghana, Togo, Guinea, and Mali. The cutoff for a positive assay was determined as > or =0.4 microg/L based on a subsample of 95 non-SW claiming abstinence for 3 months.


RESULTS
A positive PSA assay was correlated with infections with Neisseria gonorrhoeae, Chlamydia trachomatis, and Mycoplasma genitalium. Among non-SW, a positive PSA was more common among those with HIV, but less frequent in those better educated. Among SW and non-SW, women from Ghana were less likely to have a positive PSA and had a lower prevalence of sexually transmitted infections than those from elsewhere.


CONCLUSIONS
PSA can be used as a biological marker of unprotected intercourse, allowing interventions to target efforts on those at highest risk.
Pépin
Jacques
J
Department of Microbiology and Infectious Diseases, University of Sherbrooke, Sherbrooke, Quebec, Canada. jacques.pepin@usherbrooke.ca
Fink
Guy D
GD
Khonde
Nzambi
N
Sobela
Francois
F
Deslandes
Sylvie
S
Diakité
Soumaila
S
Labbé
Annie-Claude
AC
Sylla
Mohamed
M
Frost
Eric
E
D000354:Africa, Western; D005260:Female; D006801:Humans; D017430:Prostate-Specific Antigen / Q000032:analysis* / Q000378:metabolism; D047568:Unsafe Sex; D014621:Vagina / Q000378:metabolism*
D017430:Prostate-Specific Antigen