5th International AIDS Conference Montreal, Quebec, Canada — Jun 4-9, 1989

Int Conf AIDS 1989 Jun 4-9; 5:162 (abstract no. A.512)
Victorino R, Teles LC, Ferreira MO, Guerreiro D, Lourenco MH; Faculty of Medicine of Lisbon, Av. Prof. Egas Moniz - 1600 Lisbon - Portugal

OBJECTIVES: 1 - To study the prevalence of antibodies to HIV1 and HIV2 in a population of women attending a Family Planning Clinic (FPC) and a antenatal clinic (AC) serving a urban population of 30.000 people where about 10% are of African origin. 2 - Devise a protocol of a study which would maintain characteristics of the "anonymous" studies without the usual limitations of a lack of detailed clinical and epidemiological information about the individuals identified as positive for HIV. 3 - Analyse the problem of the false positive rate in a population of HIV low prevalence. MATERIAL AND

METHODS: All women attending the FCP and the AC from January 1987 to December 1988 were interviewed by a nurse and examined by a doctor, who completed a questionnaire covering relevant epidemiological and clinical information related to HIV infection. Blood was collected for routine tests in 700 women (around 80% of those attending the clinics during the period) and a sample saved for testing HIV antibodies anonymously (Elisa from I.Pasteur and Western blot in the Elisa positive cases). A second sample was obtained "anonymously" from cases who were positive in the first sample using the fact that women attend the Center regularly and blood is collected at intervals for routine tests and for this study, under code.

RESULTS: Three out the 650 Portuguese women were positive for HIV1(0.46%) and one out of 50 African women were positive for HIV2(2.0%) in the two samples collected at different times. If the criteria for defining women as seropositive did not include tests on a second sample, the number of "seropositives" in this study would be more than the double of the recorded one.

CONCLUSIONS: A representation of both HIV1 and HIV2 in this urban population was found and the importance of testing a second sample as a means of reducing false positive is documented in this study, where a protocol to repeat anonymously the blood tests was implemented, taking advantage of the special conditions in this health center.

890604
A512

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