[HIV infection in pregnant women in Dakar (Senegal)]. / L'infection par le VIH chez la femme enceinte á Dakar (Sénégal).

The epidemiologic and sociodemographic characteristics of human deficiency virus (HIV) infection vary from one country to another. The objective of this study was to determine the prevalence of HIV infection in pregnant women in Dakar and associated factors. Systematic anonymous screening was performed in pregnant women admitted to the maternity ward. Women whose seropositivity was confirmed by Western blot retroviral serology were included. One woman out of four was assigned by simple random selection to the case control group. Over a 24 month period, 12,498 women were tested. 104 were seropositive (44 HIV1, 58HIV2, and 2 HIV1-HIV2 giving a prevalence of 0.8%. Factors associated with HIV1 and HIV2 were different: mean age 21.7 years for HIV1 versus 30.6 for HIV 2 (p = 0.05); origin in Guinea-Bissau for HIV2 (p = 0.001); mean number of pregnancies 2.6 for HIV1 versus 5.9 for HIV2 (p = 0.001); mean parity 1.5 for HIV1 versus 4.5 for HIV2 (p < 0.01); vitality of the conception product in 85.1% for HIV2 versus 67.5% for HIV1 (p = 0.0001). These data confirm the low prevalence of HIV infection in pregnant women, with a predominance for HIV2. The factors identified in associated with virus type suggest a different mode of transmission and/or reduced virulence or HIV2 compared with HIV1. Knowledge of these factors helps orient management strategies, especially in pregnant women.

Risk factors for HIV-1 and HIV-2 infection in pregnant women in Dakar, Senegal.

This study examines the prevalence and risk factors for Human Immunodeficiency Virus type 1 (HIV-1) and type 2 (HIV-2) infection in pregnant women in Dakar, Senegal. From April 1991 to January 1993, 9,518 pregnant women were interviewed and serologically tested for antibodies to HIV-1 and HIV-2; 26 (0.3%) were HIV-1 seropositive, 44 (0.5%) were HIV-2 seropositive, two (0.02%) were dually seropositive, and 9,448 (99.3%) were seronegative. Guinea-Bissau nationality and age > 25 years were associated with HIV-2 infection, whereas parity < or = 2 was associated with HIV-1 infection. Among women who gave birth to live infants, shorter length of union with the partner and having been married more than once were associated with HIV-2 infection, whereas age < or = 25 years was associated with HIV-1 infection. Information gained by this study may help target intervention strategies for preventing maternal HIV infection and understanding biological differences between the two viruses.

Cost-effective diagnosis of HIV-1 and HIV-2 by recombinant-expressed env peptide (566/996) dot-blot analysis.

OBJECTIVE: To characterize the recombinant env peptides, 566 (HIV-1) and 996 (HIV-2), for their ability to serodiagnose HIV-1 and HIV-2 infection. To develop a cost-effective dot-blot format for these peptides, and to evaluate its performance in a developing country laboratory. DESIGN: The recombinant env peptides were evaluated using a select panel of sera (n = 327) with known serostatus from geographically diverse areas. A dot-blot assay was developed and tested on a second set of immunoblotted sera (n = 331) and further evaluated in the field on a third set of sera (n = 2718) from study populations. METHODS: All sera were evaluated by immunoblot with both HIV-1 and HIV-2 viral lysates. The recombinant env peptides were characterized in immunoblot assay before development of the dot-blot assay. RESULTS: The 566 (HIV-1) peptide showed 100% sensitivity and specificity. The 996 (HIV-2) peptide performed similarly, but showed the presence of HIV-1 cross-reactive epitopes. When the two env peptides were used together, there was high specificity and sensitivity for detecting HIV-positive sera in both immunoblot and dot-blot formats. The dot-blot assay performed in the field showed slightly lower specificity and sensitivity for HIV diagnosis. The relative cost of this assay combined with non-commercial immunoblot confirmation was 10-fold lower than conventional commercial assays. CONCLUSIONS: The 566 and 996 env peptides are appropriate antigens for HIV serotype diagnosis. A dot-blot assay using these peptides may be a useful cost-effective method for HIV diagnosis applicable in developing country laboratories.