Morbidity Among Human Immunodeficiency Virus-exposed but Uninfected, Human Immunodeficiency Virus-infected, and Human Immunodeficiency Virus-unexposed Infants in Zimbabwe Before Availability of Highly Active Antiretroviral Therapy

Background: Human immunodeficiency virus (HIV) remains a major cause of pediatric morbidity in Africa. In addition, HIV-exposed, but uninfected (HEU) infants can comprise a substantial proportion of all infants born in high prevalence countries and may also be a vulnerable group with special health problems.

Methods: A total of 14,110 infants were recruited within 96 hours of birth between November 1996 and January 2000. Rates and causes of sick clinic visits and hospitalizations during infancy were investigated according to infant HIV infection group: infected-intrauterine, infected-intrapartum, postnatally-infected, HEU, and not-exposed (born to HIV-negative mother).

Results: A total of 382 infected-intrauterine, 499 infected-intrapartum, 188 postnatally-infected, 2849 HEU, and 9207 not-exposed infants were included in the analysis. Compared with not-exposed infants, HIV-infected infants made 2.8 times more all-cause sick clinic visits and required 13.3 times more hospitalizations; they had 7.2 times more clinic visits and 23.5 times more hospitalizations for lower respiratory tract infection after the neonatal period and were 159.9 times more likely to be hospitalized for malnutrition during the second half of infancy. Compared with not-exposed infants, sick clinic visits were 1.2 times more common among HEU infants, were inversely associated with maternal CD4 cell count, and were significantly higher for all HEU infants except those whose mothers had a CD4 count ≥ 800 cells/μL, which was the mean value of HIV-negative women enrolled in the trial.

Conclusions: Morbidity is extremely high among HIV-infected infants. Compared with not-exposed infants, morbidity is higher among HEU infants and increases with severity of maternal disease, but is significantly higher for all mothers with CD4 cell count <800 cells/μL.