HIV incidence during pregnancy in selected Rural and Urban Health facilities in Zambia

Abstract

Despite high coverage of PMTCT services and the prevention strategies offered at ANC, new HIV infections in pregnant women are still occurring. The aim of this study was to measure the incidence of HIV during pregnancy and the relationship between new HIV infection and demographic factors. A retrospective cohort study was conducted in three of Zambia’s provinces, i.e. Central, Copperbelt and North Western. Ten health facilities were sampled conveniently by selecting those with highest attendance of ANC. Data on the demographic factors (province, residence, age, marital status, parity), the HIV test and re-test results and the time between the tests (months of observation) were extracted from the safe motherhood and PMTCT registers. Survival analysis was performed to estimate the HIV incidence and influences of demographic factors. Of the 8394 clients who initially tested negative for HIV on their first test 53 (0.6%) new infections occurred between the first and the repeat HIV test representing an overall HIV incidence of 2.3 [95%CI 1.8-3.0] per 100 person years of observation. Difference in incidence of HIV was statistically significant by demographic characteristic age not statistically significant by residence, marital status and parity and some trends where noticed. The 30-49 years age group had the highest incidence of HIV, showing a burden two-fold higher than that of the <20 years age group (3.5 vs.1.7) per 100 person years of observation P value 0.026). The incidence also tended to be higher in married women compared to single. New HIV infections observed in these pregnant women suggests presence of risky exposure to HIV infection, a pointer to limitations of past and present HIV preventive efforts. PMTCT programs are urgently advised to put much higher emphasis on HIV prevention among pregnant women found with a negative test result early in pregnancy.