HIV prevalence at birth in very low-birthweight infants

Background. South Africa implemented lifelong antiretroviral therapy (ART) for prevention of mother-to-child transmission (PMTCT) of HIV to reduce the risk of vertical HIV transmission. The rate of in utero transmission of HIV in very low-birthweight (VLBW)(< 1 500 g) infants, which is a high-risk population, is largely unknown. Objectives. To determine the rate of in utero transmission in VLBW infants and to describe the characteristics of the infants infected with HIV. Methods. This was a retrospective cross-sectional study of VLBW infants exposed to HIV, over a two-year period, at two hospitals in the Eastern Cape. Relevant data (maternal and infant) were extracted from medical records and analysed. Descriptive statistics are reported for all variables as means, medians and standard deviations for continuous numerical variables, and as percentages for categorical data. A p-value <0.05 was considered significant. Results. The hospital registers identified 273 VLBW infants; nine were excluded. Four infants (1.5%) were HIV polymerase chain reaction (PCR)-positive. The viral load was significantly higher among mothers of infants who tested HIV PCR-positive (Mann-Whitney U test; p=0.001). HIV-positive infants had a higher median weight (1 333 g v. 1 190 g) at birth; and mothers of HIV-positive infants were slightly older (31 v. 28 years). Both of these characteristics were not statistically significant. Conclusion. The study demonstrates a low prevalence of HIV in a high-risk group of VLBW infants. This rate is comparable to the national prevalence for all infants. Clinicians should aim for HIV viral suppression throughout pregnancy to achieve the global target of elimination of mother-to-child transmission.