Timing of mother-to-child transmission of HIV-1 and infant mortality in the first 6 months of life in Harare, Zimbabwe

OBJECTIVES: To examine the risks of intra-uterine (IU), intra- and early post-partum (IP/ePP) and late post-partum (LPP) mother-to-child transmission (MTCT) of HIV-1 and infant mortality in the first 6 months of life. METHODS: Whole blood was collected in ethylenediaminetetra-acetic acid at birth, 6 weeks, 3 and 6 months from 996 infants born to HIV-1 seropositive mothers. Polymerase chain reaction using Roche DNA amplification assay, version 1.5 (Roche Diagnostics Incorporation, Alameda, California, USA) was used to determine timing of MTCT. Logistic regression models determined risk factors for HIV-1 transmission and survival analyses examined mortality by timing of transmission. RESULTS: Two hundred and forty-nine mothers (30.7%) transmitted HIV-1 infection to their infants by 6 months of age. Eighty-nine infants [9.4%; 95% confidence interval (CI), 7.7-11.5], 104 infants (16.0%; 95% CI, 10.8-21.2) and 21 infants (5.3%; 95% CI, 1.6-12.2) were infected IU, IP/ePP and LPP respectively. Low maternal CD4 cell count and arm circumference were risk factors for IP/ePP transmission. Infant mortality was higher among infected infants than uninfected (P < 0.001, log rank test). Timing of infection, birth weight and maternal CD4 cell counts were important factors in predicting infant death. CONCLUSION: In the first 6 months of life, IU and IP/ePP transmission contributed more than three-quarters of the 30.7% MTCT. Our data, in addition to serving as a historical comparison, may be useful in designing and evaluating the efficacy of short course antiretroviral trials aimed at reducing MTCT in developing countries.     

HIV incidence among post-partum women in Zimbabwe: risk factors and the effect of vitamin A supplementation

OBJECTIVE: To test whether post-partum vitamin A supplementation can reduce incident HIV among post-partum women and identify risk factors for HIV incidence. DESIGN: Randomized, placebo-controlled trial METHODS: Between November 1997 and January 2001, 14,110 women were randomly administered 400,000 IU vitamin A or placebo within 96 h post-partum. HIV incidence was monitored among 9562 HIV-negative women. RESULTS: Cumulative incidence was 3.4% [95% confidence interval (CI), 3.0-3.8] and 6.5% (95% CI, 5.7-7.4) over 12 and 24 months post-partum, respectively. Vitamin A supplementation had no impact on incidence [hazard ratio (HR), 1.08; 95% CI, 0.85-1.38]. However, among 398 women for whom baseline serum retinol was measured, those with levels indicative of deficiency (< 0.7 micromol/l, 9.2% of those measured) were 10.4 (95% CI, 3.0-36.3) times more likely to seroconvert than women with higher concentrations. Furthermore, among women with low serum retinol, vitamin A supplementation tended to be protective against incidence (HR, 0.29; 95% CI, 0.03-2.60; P = 0.26), although not significantly so, perhaps due to limited statistical power. Severe anaemia (haemoglobin < 70 g/l) was associated with a 2.7-fold (95%CI, 1.2-6.1) greater incidence. Younger women were at higher risk of HIV infection: incidence declined by 5.7% (2.8-8.6) with each additional year of age. CONCLUSION: Among post-partum women, a single large-dose vitamin A supplementation had no effect on incidence, although low serum retinol was a risk factor for seroconversion. Further investigation is required to determine whether vitamin A supplementation of vitamin-A-deficient women or treatment of anaemic women can reduce HIV incidence.     

Cryptococcal osteomyelitis of the spine

We have treated seven patients with cryptococcal spondylitis. Five presented with a neurological deficit and one was HIV-positive. Amphotericin-B and 5-flucytosine were used in five patients and ketoconazole was given orally in the remaining two. Three patients made a complete neurological recovery. Since these lesions mimic spinal tuberculosis, which is commonly seen in our environment, we draw attention to the importance of obtaining a tissue diagnosis.     

Predictive value of weight loss on mortality of HIV-positive mothers in a prolonged breastfeeding setting

HIV-positive lactating women may be at high risk of weight loss due to increased caloric requirements and postpartum physiological weight loss. Ten percent weight loss is associated with a higher risk of mortality in HIV-positive patients and this alone is a criterion for highly active antiretroviral therapy (HAART) initiation where CD4 counts are not available. However, no study has investigated this association in lactating postpartum women. We investigated whether 10% weight loss predicts death in postpartum HIV-positive women. A total of 9207 HIV-negative and 4495 HIV-positive mothers were recruited at delivery. Women were weighed at 6 weeks, 3 months, and every 3 months thereafter for up to 24 months postpartum and data on mortality up to 2 years were collected. The median duration of breastfeeding was longer than 18 months. Among HIV-positive women, the independent predictors of ≥10% weight loss were CD4 cell count, body mass index, and household income. Mortality was up to 7.12 (95% CI 3.47-14.61) times higher in HIV-positive women with ≥10% weight loss than those without weight loss. Ten percent weight loss in postpartum lactating HIV-positive women was significantly predictive of death. Our findings suggest that 10% weight loss is an appropriate criterion for HAART initiation among postpartum breastfeeding women.     

HIV-1 and HIV-2 prevalence and associated risk factors among postnatal women in Harare, Zimbabwe

Studies of antenatal women form the predominant source of data on HIV-1 prevalence in Africa. Identifying factors associated with prevalent HIV is important in targeting diagnostic services and care. Between November 1997 and January 2000, 14,110 postnatal women from Harare, Zimbabwe were tested by ELISAs reactive to both HIV-1 and HIV-2; a subset of positive samples was confirmed with assays specific for HIV-1 and HIV-2. Baseline characteristics were elicited and modelled to identify risk factors for prevalent HIV infection. HIV-1 and HIV-2 prevalences were 32.0% (95% CI 31.2-32.8) and 1.3% (95% CI 1.1-1.5), respectively; 4% of HIV-1-positive and 99% of HIV-2-positive women were co-infected. HIV-1 prevalence increased from 0% among 14-year-olds to >45% among women aged 29-31 years, then fell to <20% among those aged>40 years. In multivariate analyses, prevalence increased with parity, was lower in married women than in single women, divorcees and widows, and higher in women with the lowest incomes and those professing no religion. Adjusted HIV-1 prevalence increased during 1998 and decreased during 1999. Age modified the effects of parity, home ownership and parental education. Among older women, prevalence was greater for women who were not homeowners. Among younger women, prevalence increased with parity and low parental education. None of these factors distinguished women co-infected with HIV-2 from those infected with HIV-1 alone. Prevalent HIV-1 infection is associated with financial insecurity and weak psychosocial support. The ZVITAMBO study apparently spanned the peak of the HIV-1 epidemic among reproductive women in Harare.     

Impact of Six-week Viral Load on Mortality in HIV-infected Zimbabwean Infants

Among 453 untreated HIV-infected Zimbabwean infants, 6-week viral load was the only infant factor that independently predicted mortality. Infants with viral load ≥ 1.59 million copies/mL (cohort median) had 3-fold increased mortality through 6 months (hazard ratio 3.07 [95% confidence interval: 2.16, 4.38]; P < 0.001) and 2-fold increased mortality through 12 months (hazard ratio 2.03 [95% confidence interval: 1.41, 2.91]; P < 0.001], compared with infants with viral load below the median.