Vitamin D levels in Malawian infants from birth to 24 months

We measured longitudinal levels of vitamin D in unsupplemented Malawian infants at 0 (birth), 2, 12, 15, 18 and 24 months of age. Matched maternal plasma and breast milk vitamin D(2) and D(3) levels were also measured at delivery and 2 months postpartum. Vitamin D was measured using isotope-dilution liquid chromatography tandem-mass spectrometry. Vitamin D(3) levels in children were 36% of adult levels at birth, 60% of adult levels at age 2 months, and at par with adult levels by 12 months of age. This adult-equivalent level is subsequently maintained through age 24 months and consisted of a 98% molar ratio of vitamin D(3). Vitamin D levels in breast milk were below the limit of detection, 0.1 ng/ml. Breast milk of unsupplemented Malawian mothers is a poor source of vitamin D.

Effects of cessation of breastfeeding in HIV-1-exposed, uninfected children in Malawi

BACKGROUND

We assessed morbidity rates during short intervals that accompanied weaning and cumulative mortality among HIV-exposed, uninfected infants enrolled in the postexposure prophylaxis of infants in Malawi (PEPI-Malawi) trial.

METHODS

Women were counseled to stop breastfeeding (BF) by 6 months in the PEPI-Malawi trial. HIV-uninfected infants were included in this analysis starting at age 6 months. Breastfeeding and morbidity (illness and/or hospital admission and malnutrition [weight-for-age Z-score, ≤2]) were assessed during age intervals of 6-9, 9-12, and 12-15 months. BF was defined as any BF at the start and end of the interval and no breastfeeding (NBF) was defined as NBF at any time during the interval. The association of NBF with morbidity at each mutually exclusive interval was assessed using Poisson regression models controlling for other factors. Cumulative mortality among infants aged 6-15 months with BF and NBF was assessed using an extended Kaplan-Meier method.

RESULTS

At age 6 months, 1761 HIV-uninfected infants were included in the study. The adjusted rate ratios for illnesses and/or hospital admission for NBF, compared with BF, was 1.7 (P < .0001) at 6-9 months, 1.66 (P = .0001) at 9-12 months, and 1.75 (P = .0008) at 12-15 months. The rates of morbidity were consistently higher among NBF infants during each age interval, compared with BF infants. The 15 months cumulative mortality among BF and NBF children was 3.5% and 6.4% (P = .03), respectively.

CONCLUSIONS

Cessation of BF is associated with acute morbidity events and cumulative mortality. Prolonged BF should be encouraged, in addition to close monitoring of infant health and provision of support services.

Distribution of haematological and chemical pathology values among infants in Malawi and Uganda

BACKGROUND

Data on paediatric reference laboratory values are limited for sub-Saharan Africa.

OBJECTIVE

To describe the distribution of haematological and chemical pathology values among healthy infants from Malawi and Uganda.

METHODS

A cross-sectional study was conducted among healthy infants, 0-6 months old, born to HIV-uninfected mothers recruited from two settings in Blantyre, Malawi and Kampala, Uganda. Chemical pathology and haematology parameters were determined using standard methods on blood samples. Descriptive analyses by age-group were performed based on 2004 Division of AIDS Toxicity Table age categories. Mean values and interquartile ranges were compared by site and age-group.

RESULTS

A total of 541 infants were included altogether, 294 from Malawi and 247 from Uganda. Overall, the mean laboratory values were comparable between the two sites. Mean alkaline phosphatase levels were lower among infants aged ≤21 days while aspartate aminotransferase, creatinine, total bilirubin and gamma-glutamyl transferase were higher in those aged 0-7 days than in older infants. Mean haematocrit, haemoglobin and neutrophil counts were higher in the younger age-groups (<35 days) and overall were lower than US norms. Red and white blood cell counts tended to decrease after birth but increased after ∼2 months of age. Mean basophil counts were higher in Malawi than in Uganda in infants aged 0-1 and 2-7 days; mean counts for eosinophils (for age groups 8-21 or older) and platelets (for all age groups) were higher in Ugandan than in Malawian infants. Absolute lymphocyte counts increased with infant age.

CONCLUSION

The chemical pathology and haematological values in healthy infants born to HIV-uninfected mothers were comparable in Malawi and Uganda and can serve as useful reference values in these settings.

Coverage of highly active antiretroviral therapy among postpartum women in Malawi

The expanding services of antiretroviral treatment (ART) in sub-Saharan Africa provide unique opportunities to reduce HIV/AIDS-related morbidity and mortality. In these settings, HIV prevalence among antenatal women remains high and treating eligible pregnant or breastfeeding women with antiretrovirals can substantially reduce transmission of HIV from the mother to her infant. However, identification of women eligible for treatment and ensuring access to ART services is challenging. In this analysis, we used data from a large clinical trial (the PEPI-Malawi study, 2004-09) to prevent mother-to-child transmission of HIV through extended antiretroviral prophylaxis of infants to examine barriers for wider coverage with highly active antiretroviral treatment (HAART) of postpartum women. Maternal HAART was not part of the original PEPI-Malawi clinical trial but became available through a government programme during the course of the study. Therefore, eligible women (CD4 cell count <250) who participated in the PEPI-Malawi trial were counselled and referred to the government ART clinics to initiate HAART. Of 3335 women who enrolled in the PEPI-Malawi study, 803 (24%) were eligible for HAART based on CD4 cell count. The proportion of women newly initiating HAART at the ART clinic remained low and constant (<20%) throughout the study period. However, the cumulative proportion of women receiving HAART increased substantially over time (29% in 2005 to 69% in 2009). Similarly, counselling and referral of eligible women substantially increased and became 100% during the last two years. There were no statistically significant differences in characteristics of eligible women who received or did not receive HAART postpartum. Despite limitations of not being able to obtain detailed data, the main barriers appeared to be related to the health-care system delivery of ART services. Issues of physical space, more personnel and better delivery need to be addressed to increase access to HAART in these settings.

Initiation of antiretroviral treatment in women after delivery can induce multiclass drug resistance in breastfeeding HIV-infected infants

BACKGROUND

The World Health Organization currently recommends initiation of highly active antiretroviral therapy (HAART) for human immunodeficiency virus (HIV)-infected lactating women with CD4+ cell counts <350 cells/μL or stage 3 or 4 disease. We analyzed antiretroviral drug resistance in HIV-infected infants in the Post Exposure Prophylaxis of Infants trial whose mothers initiated HAART postpartum (with a regimen of nevirapine [NVP], stavudine, and lamivudine). Infants in the trial received single-dose NVP and a week of zidovudine (ZDV) at birth; some infants also received extended daily NVP prophylaxis, with or without extended ZDV prophylaxis.

METHODS

We analyzed drug resistance in plasma samples collected from all HIV-infected infants whose mothers started HAART in the first postpartum year. Resistance testing was performed using the first plasma sample collected within 6 months after maternal HAART initiation. Categorical variables were compared by exact or trend tests; continuous variables were compared using rank-sum tests.

RESULTS

Multiclass resistance (MCR) was detected in HIV from 11 (29.7%) of 37 infants. Infants were more likely to develop MCR infection if their mothers initiated HAART earlier in the postpartum period (by 14 weeks vs after 14 weeks and up to 6 months vs after 6 months, P = .0009), or if the mother was exclusively breastfeeding at the time of HAART initiation (exclusive breastfeeding vs mixed feeding vs no breastfeeding, P = .003).

CONCLUSIONS

Postpartum maternal HAART initiation was associated with acquisition of MCR in HIV-infected breastfeeding infants. The risk was higher among infants whose mothers initiated HAART closer to the time of delivery or were still exclusively breastfeeding when they first reported HAART use.

HIV-1 incidence among women of reproductive age in Malawi

The aim of this study was to determine HIV-1 incidence among women of reproductive age in Malawi. A prospective study design was followed. HIV-1 uninfected women were followed up for nine visits during a period of 12 months. At baseline, women received HIV-1 counselling and testing. At each visit, venous blood was collected for HIV-1 testing. Incidence rate for HIV-1 was estimated using person-years of follow up (PYFU). Risk factors for HIV acquisition were assessed using Cox proportional hazard models. A total of 842 HIV-1 negative women were enrolled in the study. Of these, 787 had subsequent HIV testing and 31 were found HIV-1 infected; an overall incidence rate of 4.51 (95% confidence interval: 2.96-6.06) per 100 PYFU was obtained. Young age, using hormonal injectable contraceptives and bacterial vaginosis were the main predictors of HIV acquisition. The incidence of HIV continues to be high among women in Malawi, and young women appear to be at higher risk.

Extended antiretroviral prophylaxis to reduce breast-milk HIV-1 transmission

BACKGROUND

Effective strategies are urgently needed to reduce mother-to-child transmission of human immunodeficiency virus type 1 (HIV-1) through breast-feeding in resource-limited settings.

METHODS

Women with HIV-1 infection who were breast-feeding infants were enrolled in a randomized, phase 3 trial in Blantyre, Malawi. At birth, the infants were randomly assigned to one of three regimens: single-dose nevirapine plus 1 week of zidovudine (control regimen) or the control regimen plus daily extended prophylaxis either with nevirapine (extended nevirapine) or with nevirapine plus zidovudine (extended dual prophylaxis) until the age of 14 weeks. Using Kaplan-Meier analyses, we assessed the risk of HIV-1 infection among infants who were HIV-1-negative on DNA polymerase-chain-reaction assay at birth.

RESULTS

Among 3016 infants in the study, the control group had consistently higher rates of HIV-1 infection from the age of 6 weeks through 18 months. At 9 months, the estimated rate of HIV-1 infection (the primary end point) was 10.6% in the control group, as compared with 5.2% in the extended-nevirapine group (P<0.001) and 6.4% in the extended-dual-prophylaxis group (P=0.002). There were no significant differences between the two extended-prophylaxis groups. The frequency of breast-feeding did not differ significantly among the study groups. Infants receiving extended dual prophylaxis had a significant increase in the number of adverse events (primarily neutropenia) that were deemed to be possibly related to a study drug.

CONCLUSIONS

Extended prophylaxis with nevirapine or with nevirapine and zidovudine for the first 14 weeks of life significantly reduced postnatal HIV-1 infection in 9-month-old infants. (ClinicalTrials.gov number, NCT00115648.)

Late postnatal transmission of HIV-1 and associated factors

BACKGROUND

The present study was undertaken to determine the risk and timing of late postnatal transmission (LPT) of human immunodeficiency virus type 1 (HIV-1).

METHODS

Breast-fed infants previously enrolled in 2 trials of antiretroviral prophylaxis were monitored in Malawi. Kaplan-Meier and proportional hazard models assessed cumulative incidence and association of factors with LPT.

RESULTS

Overall, 98 infants were HIV infected, and 1158 were uninfected. The cumulative risk of LPT at age 24 months was 9.68% (95% confidence interval, 7.80%-11.56%). The interval hazards at 1.5-6, 6-12, 12-18, and 18-24 months were 1.22%, 4.05%, 3.48%, and 1.27%, respectively.

CONCLUSIONS

The risk of LPT beyond 6 months is substantial. Weaning at 6 months could prevent >85% of LPT.

Intermittent intravaginal antibiotic treatment of bacterial vaginosis in HIV-uninfected and -infected women: a randomized clinical trial

Objective:

Assess efficacy of intermittent intravaginal metronidazole gel treatment in reducing frequency of bacterial vaginosis (BV).

Design:

Randomized, double-masked, placebo-controlled phase 3 trial.

Setting:

Postnatal and family planning clinics of the Queen Elizabeth Central Hospital and two health centers in Blantyre, Malawi.

Participants:

Nonpregnant HIV-uninfected and -infected women.

Intervention:

Intravaginal metronidazole treatment and placebo gels provided at baseline and every 3 mo for 1 y.

Outcome measures:

Primary: Cross-sectional and longitudinal comparisons of BV frequency at baseline, 1 mo after product dispensation (post-treatment evaluation [PTE]), and every quarterly visit. Secondary: Effect of treatment on BV clearance and recurrence.

Results:

Baseline: 842 HIV-uninfected and 844 HIV-infected women were enrolled. The frequency of BV at baseline in treatment and placebo arms, respectively, was 45.9% and 46.8% among HIV-uninfected women, and 60.5% and 56.9% among HIV-infected women. Primary outcomes: At the PTEs the prevalence of BV was consistently lower in treatment than placebo arms irrespective of HIV status. The differences were statistically significant mainly in HIV-uninfected women. Prevalence of BV was also reduced over time in both treatment and placebo arms. In a multivariable analysis that controlled for other covariates, the effect of intravaginal metronidazole treatment gel compared with placebo was not substantial: adjusted relative risk (RR) 0.90, 95% confidence interval (CI) 0.83–0.97 in HIV-uninfected women and adjusted RR 0.95, 95% CI 0.89–1.01 in HIV-infected women. Secondary outcomes: Intravaginal metronidazole treatment gel significantly increased BV clearance (adjusted hazard ratio [HR] 1.34, 95% CI 1.07–1.67 among HIV-uninfected women and adjusted HR 1.29, 95% CI 1.06–1.58 among HIV-infected women) but was not associated with decreased BV recurrence. Safety: No serious adverse events were related to use of intravaginal gels.

Conclusion:

Intermittent microbicide treatment with intravaginal gels is an innovative approach that can reduce the frequency of vaginal infections such as BV.

Background: Bacterial vaginosis (BV) results from a change in the normal balance of bacteria in the vaginal tract, and is very common. In pregnant women, it is associated with poorer outcomes in pregnancy, and is also linked with HIV transmission (although it is not certain that BV actually increases the chance of getting HIV—just because these two occur together it does not necessarily follow that one causes the other). BV can be treated with metronidazole tablets, although these can cause gut symptoms and should not be taken repeatedly. The researchers wanted to carry out a multiclinic–based trial to find out whether a metronidazole gel applied intermittently to the vagina (for five nights every three months) would reduce the frequency of BV among women in Malawi. HIV-infected and HIV-uninfected women, recruited from postnatal and family planning clinics, were randomized to receive either metronidazole gels, or equivalent placebo gels, every three months and were then followed up for 12 months. The primary outcome for the trial was the proportion of women with BV at each quarterly follow-up visit, and the researchers intended to compare this outcome between treatment arms at each visit and also to look at the overall changes over time among women receiving either metronidazole or placebo, looking separately at HIV-infected and HIV-uninfected women.

What this trial shows: In total 1,686 women took part in the trial (842 not infected with HIV, and 844 infected with HIV). The proportion of HIV-uninfected women with BV dropped by around 20% over the course of the trial, both in women using metronidazole and in those using placebo. However, when comparing the proportion of HIV-uninfected women with BV between the two arms of the trial, there did not seem to be a consistent effect: differences were statistically significant at some time points and not others. Among HIV-infected women, there was also a drop over the course of the trial in the proportion of women with BV, irrespective of whether they used metronidazole or placebo. Again, when comparing the rate of BV among HIV-infected women between study arms (metronidazole versus placebo), the researchers did not see a consistent trend; differences were statistically significant at some time points but not others. Overall, when comparing metronidazole and placebo in an analysis that controlled for other factors, the metronidazole gel seemed to show a small effect in reduction of BV among HIV-uninfected women, but no obvious effect among HIV-infected women.

Strengths and limitations: Strengths in the design of this trial include the sample size, which was appropriate to detect an important effect of the metronidazole gel (versus placebo) had one existed, and the randomization and blinding procedures, which were designed to minimize the chance that the trialists or women being enrolled could anticipate to which arm of the trial they might be assigned. A key limitation of this study, as the researchers acknowledge, is the absence of a “no treatment” study arm. The frequency of BV dropped over the course of the trial in women using the placebo gel, raising the possibility that the placebo actually has some effect on bacteria in the vagina. However, a trial with a “no treatment” arm would pose its own problems, since trialists and participants would then not be fully blinded as to their treatment status.

Contribution to the evidence: This trial adds data on the efficacy of metronidazole gel when used intermittently, and among women in the community who may or may not actually have BV. Previous studies have evaluated treatment with metronidazole among women who already have symptoms or a diagnosis of BV. The findings of this trial rule out a substantial effect of metronidazole gel, as compared to placebo gel, in reducing the frequency of BV in this setting.

The impact of breastfeeding on the health of HIV-positive mothers and their children in sub-Saharan Africa

OBJECTIVE

We assessed the impact of breastfeeding by women infected with human immunodeficiency virus (HIV)-1 on their morbidity and risk of mortality and on the mortality of their children.

METHODS

We analysed longitudinal data from two previous randomized clinical trials of mother-to-child transmission of HIV conducted between April 2000 and March 2003 in the Republic of Malawi, Africa. Mothers infected with HIV, and their newborns, were enrolled at the time of their child's birth; they then returned for follow-up visits when the child was aged 1 week, 6-8 weeks and then 3, 6, 9, 15, 18, 21 and 24 months. Patterns of breastfeeding (classified as exclusive, mixed or no breastfeeding), maternal morbidity and mortality, and mortality among their children were assessed at each visit. Descriptive and multivariate analyses were performed to determine the association between breastfeeding and maternal and infant outcomes.

FINDINGS

A total of 2000 women infected with HIV were enrolled in the original studies. During the 2 years after birth, 44 (2.2%) mothers and 310 (15.5%) children died. (Multiple births were excluded.) The median duration of breastfeeding was 18 months (interquartile range (IQR)=9.0-22.5), exclusive breastfeeding 2 months (IQR=2-3) and mixed feeding 12 months (IQR=6-18). Breastfeeding patterns were not significantly associated with maternal mortality or morbidity after adjusting for maternal viral load and other covariates. Breastfeeding was associated with reduced mortality among infants and children: the adjusted hazard ratio for overall breastfeeding was 0.44 (95% confidence interval (CI)=0.28-0.70), for mixed feeding 0.45 (95% CI=0.28-0.71) and for exclusive breastfeeding 0.40 (95% CI=0.22-0.72). These protective effects were seen both in infants who were infected with HIV and those who were not.

CONCLUSION

Breastfeeding by women infected with HIV was not associated with mortality or morbidity; it was associated with highly significant reductions in mortality among their children.

Development of nevirapine resistance in infants is reduced by use of infant-only single-dose nevirapine plus zidovudine postexposure prophylaxis for the prevention of mother-to-child transmission of HIV-1

We analyzed the development of nevirapine (NVP) resistance in human immunodeficiency virus type 1 (HIV-1)-infected Malawian infants who received regimens containing single-dose NVP (SD-NVP) for the prevention of mother-to-child transmission (MTCT) of HIV-1. All infants received SD-NVP, and some randomly received zidovudine (ZDV) as well. Mothers did or did not receive SD-NVP on the basis of when they arrived at the hospital for delivery. In infants 6-8 weeks of age, NVP resistance was less frequent when infants had received SD-NVP plus ZDV and mothers had not received SD-NVP than when infants had received SD-NVP alone and mothers had received SD-NVP (4/15 [27%] vs. 20/23 [87%]; P < .001). The risk of MTCT of HIV-1 was comparable with these regimens. Infant-only prophylaxis also eliminates the development of NVP resistance in mothers.

Gender differences in perinatal HIV acquisition among African infants

OBJECTIVE

We investigated gender-specific risks of mother-to-child transmission (MTCT) at birth and at 6 to 8 weeks among infants born to HIV-infected African women.

DESIGN

Follow-up study of infants enrolled in 2 randomized, phase III, clinical trials to prevent MTCT, conducted in Blantyre, Malawi, in southeast Africa.

METHODS

Infants were enrolled at birth and monitored postnatally, and their HIV status was assessed at birth and at 6 to 8 weeks (assessment beyond 6-8 weeks is ongoing). Statistical analyses were stratified according to gender, and comparisons were made with descriptive, univariate, and multivariate statistical tests. MTCT was estimated at birth and at 6 to 8 weeks among infants who were not infected at birth.

RESULTS

Overall, 966 boys and 998 girls were enrolled. The rate of HIV transmission at birth was 9.5% (187 of 1964 infants). However, at birth significantly more girls (12.6%) than boys (6.3%) were infected with HIV. This association remained significant after controlling for maternal viral load and other factors. Among infants who were uninfected at birth, 8.7% (135 of 1554 infants) acquired HIV by 6 to 8 weeks; of these infants, more girls acquired HIV (10.0%), compared with boys (7.4%).

CONCLUSIONS

Female infants may be more susceptible to HIV infection before birth and continuing after birth. Alternatively, in utero mortality rates of HIV-infected male infants may be disproportionately higher and thus more HIV-infected female infants are born. In areas of sub-Saharan Africa, where HIV infection rates are high among women of reproductive age, the magnitude of the gender transmission differences observed in this study could have clinical, preventive, and demographic implications.

Nonoxynol-9 100 mg gel: multi-site safety study from sub-Saharan Africa

OBJECTIVES

To evaluate the safety of 100 mg nonoxynol-9 (N-9) gel, a vaginal microbicide, on the genital mucosa of women from Malawi and Zimbabwe in preparation for a phase III efficacy study.

METHODS

HIV-uninfected women (180) were enrolled and randomized to either N-9 or placebo gel and instructed to insert gel into the vagina twice daily for 14 days. Follow up examinations were conducted at 7 and 14 days.

RESULTS

The number of adverse events in the N-9 gel group was higher than in the placebo group (40% versus 13%; P < 0.01). Reported number of any genital symptoms was significantly higher in the N-9 group (38% N-9, 13% placebo; P = 0.01). The number of total epithelial disruptions was higher in the N-9 group (20% versus 3%; P < 0.01); however, the number of genital ulcers and abrasions in the N-9 group was low (2% and 3%, respectively) and not different from that in the placebo group (1% and 2%, respectively).

CONCLUSIONS

N-9 gel 100 mg caused a significant increase in the rate of genital symptoms and epithelial disruptions compared with placebo. The clinical significance of these epithelial disruptions is unknown. Although these findings alone were not sufficient to cancel the planned phase III study, when considered together with the negative results from the COL-1492 effectiveness trial of 52.5 mg N-9 gel, the decision was made to cancel the planned phase III trial of 100 mg N-9 gel.

Nevirapine and zidovudine at birth to reduce perinatal transmission of HIV in an African setting: a randomized controlled trial

CONTEXT

Antenatal counseling and human immunodeficiency virus (HIV) testing are not universal in Africa; thus, women often present in labor with unknown HIV status without receiving the HIVNET 012 nevirapine (NVP) regimen (a single oral dose of NVP to the mother at the start of labor and to the infant within 72 hours of birth).

OBJECTIVE

To determine risk of mother-to-child transmission of HIV when either standard use of NVP alone or in combination with zidovudine (ZDV) was administered to infants of women tested at delivery.

DESIGN, SETTING, AND PARTICIPANTS

A randomized, open-label, phase 3 trial conducted between April 1, 2000, and March 15, 2003, at 6 clinics in Blantyre, Malawi, Africa. The trial included all infants born to 894 women who were HIV positive, received NVP intrapartum, and were previously antiretroviral treatment-naive. Infants were randomly assigned to NVP (n = 448) and NVP plus ZDV (n = 446). Infants were enrolled at birth, observed at 6 to 8 weeks, and followed up through 3 to 18 months. The HIV status of 90% of all infants was established at 6 to 8 weeks.

INTERVENTION

Mothers received a 200-mg single oral dose of NVP intrapartum and infants received either 2-mg/kg oral dose of NVP or NVP (same dose) plus 4 mg/kg of ZDV twice per day for a week.

MAIN OUTCOME MEASURES

HIV infection of infant at birth and 6 to 8 weeks, and adverse events.

RESULTS

The mother-to-child transmission of HIV at birth was 8.1% (36/445) in infants administered NVP only and 10.1% (45/444) in those administered NVP plus ZDV (P =.30). A life table estimate of transmission at 6 to 8 weeks was 14.1% (95% confidence interval [CI], 10.7%-17.4%) in infants who received NVP and 16.3% (95% CI, 12.7%-19.8%) in those who received NVP plus ZDV (P =.36). For infants not infected at birth and retested at 6 to 8 weeks, transmission was 6.5% (23/353) in those who received NVP only and 6.9% (25/363) in those who received NVP plus ZDV (P =.88). Almost all infants (99%-100%) were breastfed at 1 week and 6 to 8 weeks. Grades 3 and 4 adverse events were comparable; 4.9% (22/448) and 5.4% (24/446) in infants receiving NVP only and NVP plus ZDV, respectively (P =.76).

CONCLUSIONS

The frequency of mother-to-child HIV transmission at 6 to 8 weeks in our 2 study groups was comparable with that observed for other perinatal HIV intervention studies among breastfeeding women in Africa. The safety of the regimen containing neonatal ZDV was similar to that of a standard NVP regimen.

Short postexposure prophylaxis in newborn babies to reduce mother-to-child transmission of HIV-1: NVAZ randomised clinical trial

BACKGROUND

In sub-Saharan Africa, most women present late for delivery with unknown HIV status, which limits the use of intrapartum nevirapine to prevent mother-to-child transmission of HIV. We aimed to determine whether post-exposure prophylaxis of nevirapine plus zidovudine given to babies only reduced transmission of HIV more than did a regimen of nevirapine alone.

METHODS

We randomly assigned 1119 babies of Malawian women with HIV-1 who presented late (ie, within 2 h of expected delivery) to either nevirapine alone or nevirapine and zidovudine. Both drugs were given immediately after birth: one dose of nevirapine (2 mg/kg weight) was given as a single dose; babies in the nevirapine plus zidovudine group also received zidovudine twice daily for 1 week (4 mg/kg weight). Infant HIV infection was determined at birth and at 6-8 weeks. Primary outcome was HIV infection in babies at 6-8 weeks in those not infected at birth. Analysis was by intention to treat.

FINDINGS

The overall rate of mother-to-child transmission at 6-8 weeks was 15.3% in 484 babies who received nevirapine and zidovudine and 20.9% in 468 babies who received nevirapine only (p=0.03). At 6-8 weeks, in babies who were HIV negative at birth, 34 (7.7%) babies who had nevirapine and zidovudine and 51 (12.1%) who received nevirapine only were infected (p=0.03)-a protective efficacy of 36%. This finding remained after controlling for maternal viral load and other factors at baseline. Adverse events were mild and of similar frequency in the two groups.

INTERPRETATION

Postexposure prophylaxis can offer protection against HIV infection to babies of women who missed opportunities to be counselled and tested before or during pregnancy. The nevirapine and zidovudine regimen is safe and easy to implement.

HIV-1 prevalence and herpes simplex virus 2, hepatitis C virus, and hepatitis B virus infections among male workers at a sugar estate in Malawi

HIV-1 prevalence is approximately 23% among men working at a sugar estate in Malawi. Given the scale of the HIV epidemic in this country, it is important to determine possible cofactors of infection. The authors investigated associations between HIV-1 prevalence and herpes simplex virus 2 (HSV-2), hepatitis C virus (HCV), and hepatitis B virus (HBV) infections (indicated by anti-HSV-2, anti-HCV and HBsAg positivity, respectively) in a nested case-control study of 279 HIV-positive and 280 HIV-negative male workers. The prevalence of HSV-2 infection was 88.1% among HIV-positive persons and 64.3% among HIV-negative control subjects (p <.01). This difference persisted after adjusting for sexual behavior and history of sexually transmitted diseases (OR = 4.12; 95% CI, 2.21-7.68). The prevalence of HCV seropositivity was 12.7% among HIV-positive persons and 10.0% among control subjects (p =.31), whereas that of HBV infection was 16.9% among HIV-positive persons and 14.4% among control subjects (p =.46). HSV-2 infection is significantly associated with prevalent HIV-1 infection in this population. Therefore, preventive measures for HSV-2 and HIV infection should be emphasized.

Three surveys of HIV-1 prevalence and risk factors among men working at a sugar estate in Malawi

BACKGROUND

HIV-1 surveys in defined populations identify underlying risks and trends useful to mount interventions.

GOAL

The goal of the study was to determine HIV-1 prevalence and risk factors among men working at a Malawian sugar estate.

STUDY DESIGN

Three independent surveys were conducted in 1994, 1997, and 1998. Procedures included obtaining informed consent, interviewing, and drawing blood for HIV and syphilis testing. Analyses determined prevalence of HIV and associated risk factors.

RESULTS

HIV prevalence was 24.3% in 1994 (n = 1691), 22.8% in 1997 (n = 615), and 20.9% in 1998 (n = 1354; P < 0.03). From 1994 to 1998, the percentage of subjects with a history of sexually transmitted disease (STD) decreased from 43.6% to 29.5% (P < 0.0001), accompanied by a substantial rise in STDs confirmed by physical examination (from 7.5% to 16.8%; P < 0.0001) and by laboratory testing for syphilis (from 6.5% to 10.4%; P < 0.0001). The percentage with multiple sex partners declined (from 62.0% to 35.2%; P < 0.0001), and condom use rose (from 10.9% to 18.9%; P < 0.0001). STDs were significantly associated with prevalent HIV infection each year.

CONCLUSIONS

The prevalence of HIV has remained relatively stable and high in this cohort.

HIV-1 incidence among male workers at a sugar estate in rural Malawi

OBJECTIVES

To determine incidence of HIV and associated risk factors in two cohorts of men working at a sugar estate in rural Malawi.

DESIGN

Prospective studies.

METHODS

After counseling and obtaining informed consent, male workers were tested for HIV-1 and syphilis. Baseline HIV-seronegative men were enrolled in two follow-up studies in 1994 and 1998, and were retested for HIV and syphilis at 6-month follow-up visits. Demographic, behavioral, and medical history was collected at baseline. Cumulative HIV incidence based on Kaplan-Meier methods was estimated. HIV incidence was also estimated per 100 person-years (p-y). Crude and adjusted rate ratios for the association of risk factors with incident HIV infection were obtained using Cox proportional hazards models.

RESULTS

HIV prevalence was 24.3% among 1692 men screened in 1994 and 21.0% among 1349 men screened in 1998 (p <.03). HIV incidence was extremely high during 1994 to 1995 (17.1% for that 1-year period). Incidence dramatically declined in 1996, averaging about 3.5% per year from 1996 through 1999. Among men enrolled in the 1998 cohort, HIV incidence during 1998 to 1999 was 3.8%. After controlling for potential confounders reactive syphilis was associated with a twofold risk of HIV acquisition in each cohort.

CONCLUSIONS

Urgent preventive measures are needed to control the spread of HIV in this economically important occupational cohort. In addition to conventional educational messages to reduce risky sexual behavior, treatment of other sexually transmitted diseases should be considered.

Morbidity among human immunodeficiency virus-1-infected and -uninfected African children

OBJECTIVE

To assess patterns of morbidity and associated factors in late infancy and early childhood among human immunodeficiency virus (HIV)-infected and -uninfected African children.

DESIGN

Prospective study.

SETTING

The Queen Elizabeth Central Hospital, Blantyre, Malawi.

PARTICIPANTS

Children with known HIV status from an earlier perinatal intervention trial were enrolled during the first year of life and followed to approximately 36 months of age.

OUTCOME MEASURES

Morbidity and mortality information was collected every 3 months by a questionnaire. A physical examination was conducted every 6 months. Blood to determine CD4(+) values was also collected. Age-adjusted and Kaplan-Meier analyses were performed to compare rates of morbidity and mortality among infected and uninfected children.

RESULTS

Overall, 808 children (190 HIV-infected, 499 HIV-uninfected but born to infected mothers, and 119 born to HIV-uninfected mothers) were included in this study. Of these, 109 died during a median follow-up of 18 months. Rates of childhood immunizations were high among all children (eg, lowest was measles vaccination [87%] among HIV-infected children). Age-adjusted morbidity rates were significantly higher among HIV-infected than among HIV-uninfected children. HIV-infected children were more immunosuppressed than were uninfected children. By 3 years of age, 89% of the infected children died, 10% were in HIV disease category B or C, and only approximately 1% were without HIV symptoms. Among HIV-infected children, median survival after the first occurrence of acquired immunodeficiency syndrome-related conditions, such as splenomegaly, oral thrush, and developmental delay, was <10 months. These same conditions, in addition to frequent bouts of fever, were the main morbidity predictors of mortality.

CONCLUSIONS

The frequency of diseases was high, and progression from asymptomatic or symptomatic HIV disease to death was rapid. Management strategies that effectively reduce morbidity for HIV-infected children are needed.

Association of HIV-1 load and CD4 lymphocyte count with mortality among untreated African children over one year of age

OBJECTIVE

To examine the association of viral load and CD4 lymphocyte count with mortality among HIV-infected children over one year of age.

DESIGN

A prospective study. HIV-infected children were enrolled during the first year of life and followed for more than 2 years at the Queen Elizabeth Central Hospital in Blantyre, Malawi (southeast Africa).

METHODS

Morbidity and mortality information was collected every 3 months, and physical examination and blood testing (for viral level and CD4 cell percentage) were performed every 6 months. Kaplan-Meier analyses and proportional hazards models were used to estimate survival and to examine the association of primary predictors with mortality.

RESULTS

Of 155 HIV-infected children originally enrolled, 115 (74%) had viral load testing and 82 (53%) had both viral load and CD4 cell percentage testing after their first year. Among children over one year of age, significant associations were found between mortality and the log10 viral load and CD4 cell percentage in both univariate and multivariate models. Independent of the CD4 cell value, a one unit log10 increase in HIV RNA level increased the hazard of child mortality by more than twofold. Children with low CD4 cell counts (< 15%) and high viral loads (> or = 250,000 copies/ml median value) had the worst survival; children with high CD4 cell counts (> or = 15%) and low viral loads (< 250,000 copies/ml) had the best survival.

CONCLUSION

As in developed countries, viral load and CD4 cell count are the main predictors of mortality among African children. Making these tests available adds to the challenges to be considered if antiviral therapies were to be adopted in these countries.

HIV transmission through breastfeeding: a study in Malawi

CONTEXT

Understanding the risk of human immunodeficiency virus (HIV) transmission through breastfeeding is essential for advising HIV-infected mothers and formulating public health policy recommendations.

OBJECTIVE

To measure the frequency, timing, and risk factors of HIV transmission through breast milk.

DESIGN

Prospective cohort study conducted between 1994 and 1997, with follow-up of infants through 24 months of age.

SETTING

Postnatal clinic of tertiary care hospital, Blantyre, Malawi.

PARTICIPANTS

A total of 672 infants (HIV-negative at birth) born to HIV-infected women who had not received antiretroviral drugs during or after pregnancy.

MAIN OUTCOME MEASURE

Incidence of HIV in breastfed infants by age and maternal and infant risk factors for HIV transmission, using proportional hazard models to derive risk ratios (RRs) and 95% confidence intervals (CIs).

RESULTS

Forty-seven children became HIV-infected while breastfeeding but none after breastfeeding had stopped. The cumulative infection rate while breastfeeding, from month 1 to the end of months 5, 11,17, and 23, was 3.5%, 7.0%, 8.9%, and 10.3%, respectively. Incidence per month was 0.7% during age 1 to 5 months, 0.6% during age 6 to 11 months, and 0.3% during age 12 to 17 months (P = .01 for trend). The only factors significantly associated with low risk of postnatal HIV transmission in a multivariate model were high maternal parity (RR, 0.23; 95% CI, 0.09-0.56) and older maternal age (RR, 0.44; 95% CI, 0.23-0.84).

CONCLUSIONS

Our data suggest that the risk of HIV infection is highest in the early months of breastfeeding, which should be considered in formulating breastfeeding policy recommendations.

Mortality after the first year of life among human immunodeficiency virus type 1-infected and uninfected children

BACKGROUND

HIV-infected and uninfected children who survived their first year of life were prospectively followed in Malawi to assess levels of mortality and related risk factors during the second and third years of life.

METHODS

Children with known HIV status from an earlier perinatal intervention trial were enrolled. These children [HIV-infected (Group A); HIV-uninfected but born to HIV-seropositive mothers (Group B); and children born to HIV-seronegative mothers (Group C)] were followed every 3 months until age 36 months. Mortality data were collected at each visit. Immunologic data (CD4+ percent) were collected at or immediately after enrollment.

RESULTS

Overall 702 children were enrolled and 83 children died during follow-up. The mortality rate per 1000 person years of observation was 339.3 among Group A children, 46.3 among Group B children and 35.7 among Group C children. Among HIV-infected children the cumulative proportion surviving to age 24 months was 70% and those surviving to age 36 months was 55%. By age 32 months none of the severely immunosuppressed (CD4% < 15%) children had survived. The mortality differentials between HIV-infected and uninfected children persisted after adjusting for several risk factors. The major causes of death among infected children (n = 52) were wasting and respiratory conditions.

CONCLUSIONS

Although all HIV-infected children had received childhood immunizations, mortality was high. Management of these children should include aggressive antimicrobial treatment, and evaluation of prophylactic regimens should be considered.

HIV infection and disturbances of vaginal flora during pregnancy

Disturbances of vaginal flora are common among women of reproductive age. In areas of sub-Saharan Africa where the prevalence of HIV is high, the frequency of bacterial vaginosis (BV) is also high. In this study, we assessed the association of BV and other disturbances of vaginal flora with prevalent HIV infection in two cross-sectional studies among pregnant women in urban Malawi. The prevalence of HIV-1 was 23% in 1990 and 30% in 1993. Overall, 30% of the women had BV, 59% had mild or moderate disturbance of vaginal flora, and only 11% had normal vaginal flora. Increasing prevalence of HIV was significantly associated with increasing severity of disturbance of vaginal flora (p < .00001, chi2 trend test). This trend of increased prevalence persisted after controlling for concurrent sexually transmitted diseases (STDs), sexual activity, and socioeconomic factors. After multivariate adjustment for potential confounders, the odds ratio for the association of BV with prevalent HIV infection was 3.0 (95% confidence interval [CI], 2.4-3.8), that of moderate vaginal disturbance with HIV infection was 2.2 (95% CI, 1.7-2.8), and that of mild vaginal disturbance with HIV infection was 1.6 (95% CI, 1.3-2.1). Among women with BV, HIV infection was higher among younger women than older, implying more recent infection. Although these studies were cross-sectional, our data suggest that BV could be associated with increased susceptibility to HIV infection.

Bacterial vaginosis and disturbances of vaginal flora: association with increased acquisition of HIV

BACKGROUND

Cross-sectional studies suggest an association between bacterial vaginosis (BV) and HIV-1 infection. However, an assessment of a temporal effect was not possible.

OBJECTIVES

To determine the association of BV and other disturbances of vaginal flora with HIV seroconversion among pregnant and postnatal women in Malawi, Africa.

DESIGN

Longitudinal follow-up of pregnant and postpartum women.

METHODS

Women attending their first antenatal care visit were screened for HIV after counselling and obtaining informed consent. HIV-seronegative women were enrolled and followed during pregnancy and after delivery. These women were again tested for HIV at delivery and at 6-monthly visits postnatally. Clinical examinations and collection of laboratory specimens (for BV and sexually transmitted diseases) were conducted at screening and at the postnatal 6-monthly visits. The diagnosis of BV was based on clinical criteria. Associations of BV and other risk factors with HIV seroconversion, were examined using contingency tables and multiple logistic regression analyses on antenatal data, and Kaplan-Meier proportional hazards analyses on postnatal data.

RESULTS

Among 1196 HIV-seronegative women who were followed antenatally for a median of 3.4 months, 27 women seroconverted by time of delivery. Postnatally, 97 seroconversions occurred among 1169 seronegative women who were followed for a median of 2.5 years. Bacterial vaginosis was significantly associated with antenatal HIV seroconversion (adjusted odds ratio = 3.7) and postnatal HIV seroconversion (adjusted rate ratio = 2.3). There was a significant trend of increased risk of HIV seroconversion with increasing severity of vaginal disturbance among both antenatal and postnatal women. The approximate attributable risk of BV alone was 23% for antenatal HIV seroconversions and 14% for postnatal seroconversions.

CONCLUSIONS

This prospective study suggests that progressively greater disturbances of vaginal flora, increase HIV acquisition during pregnancy and postnatally. The screening and treating of women with BV could restore normal flora and reduce their susceptibility to HIV.

Trends of HIV-1 and sexually transmitted diseases among pregnant and postpartum women in urban Malawi

OBJECTIVES

To examine rates of HIV-1 and sexually transmitted disease (STD) among pregnant and postpartum women in urban Malawi, Africa.

DESIGN

Serial cross-sectional surveys and a prospective study.

METHODS

Three major surveys were conducted in 1990, 1993 and 1994/1995. Consecutive first-visit antenatal women and women giving birth at the Queen Elizabeth Central Hospital were tested for HIV and STD after counseling and obtaining informed consent. Unlinked, anonymous HIV testing was also conducted on smaller samples of antenatal women in the same hospital to provide annual prevalence data. HIV-seronegative postpartum women from the 1990 and 1993 surveys were enrolled in a prospective study to determine HIV incidence.

RESULTS

HIV seroprevalence rose from 2.0% in 1985 to 32.8% in 1996, a 16-fold increase. The highest age-specific HIV prevalence was in the following age-groups: 20-24 years during 1990, 25-29 years during 1993, and 30-34 years during 1996. Among 1173 women followed for a median of 30.9 months, HIV incidence was 5.98 per 100 person-years in women aged < 20 years and declined steadily in older women. The prevalence of STD significantly declined among both HIV-positive and negative women. This decline in STD prevalence, however, was not accompanied by increased condom use over time.

CONCLUSIONS

Among urban childbearing women in Malawi, incidence of HIV is highest among young women while, currently, prevalence is highest among older women. Recent declines in STD prevalence suggest that HIV prevention programs are having an impact either through improved STD diagnosis and treatment or reduced risk behaviors. Sequential cross-sectional STD prevalence measures may be useful in monitoring effectiveness of STD and HIV prevention activities.