Computer-Aided Diagnosis System for Alzheimer's Disease Using Different Discrete Transform Techniques

The different discrete transform techniques such as discrete cosine transform (DCT), discrete sine transform (DST), discrete wavelet transform (DWT), and mel-scale frequency cepstral coefficients (MFCCs) are powerful feature extraction techniques. This article presents a proposed computer-aided diagnosis (CAD) system for extracting the most effective and significant features of Alzheimer's disease (AD) using these different discrete transform techniques and MFCC techniques. Linear support vector machine has been used as a classifier in this article. Experimental results conclude that the proposed CAD system using MFCC technique for AD recognition has a great improvement for the system performance with small number of significant extracted features, as compared with the CAD system based on DCT, DST, DWT, and the hybrid combination methods of the different transform techniques.

Seroprevalence for Hepatitis E and Other Viral Hepatitides among Diverse Populations, Malawi

Analysis of blood samples collected over 20 years suggests substantial underestimation of this virus in this country.

Data on prevalence of hepatitis E virus (HEV) in Malawi is limited. We tested blood samples from HIV-uninfected and -infected populations of women and men enrolled in research studies in Malawi during 1989–2008 to determine the seroprevalence of HEV, hepatitis A virus (HAV), hepatitis B virus (HBV), and hepatitis C virus (HCV). Samples were tested for IgG against HEV, total antibodies against HAV and HCV, and presence of HBV surface antigens. Of 800 samples tested, 16.5% were positive for HEV IgG, 99.6% were positive for HAV antibodies, 7.5% were positive for HBV surface antigen, and 7.1% were positive for HCV antibodies. No clear trends over time were observed in the seroprevalence of HEV, and HIV status was not associated with hepatitis seroprevalence. These preliminary data suggest that the seroprevalence of HEV is high in Malawi; the clinical effects may be unrecognized or routinely misclassified.

Climate Change and Potential Impact on Disease: What are the Public Health Agenda?

Globally, the impact of climate change on human health is widely discussed. There are several mechanisms how environmental variability can influence the occurrence of diseases that are communicable or noncommunicable. The biophysical underlying causes of climate changes are not proportionately distributed between developed and developing countries. Developed countries contribute more greenhouse emissions, but the population health effects of climate change are estimated to be higher in developing countries compared to developed countries. Therefore, examination of challenges associated with climate change should be a priority. In the countries of North Africa and the Middle East, a clear public health agenda needs to be developed, even if local/regional factors contributing to unpredictable climatic changes are not well-known. Targeting risk factors associated with noncommunicable diseases, and adopting lifestyle changes are interventions to consider.

Evaluation of postpartum HIV superinfection and mother-to-child transmission

OBJECTIVE

This study examined HIV superinfection in HIV-infected women postpartum, and its association with mother-to-child transmission (MTCT).

DESIGN

Plasma samples were obtained from HIV-infected women who transmitted HIV to their infants after 6 weeks of age (transmitters, n = 91) and HIV-infected women who did not transmit HIV to their infants (nontransmitters, n = 91). These women were originally enrolled in a randomized trial for prevention of MTCT of HIV in Malawi (Post-Exposure Prophylaxis of Infants trial in Malawi).

METHODS

Two HIV genomic regions (p24 and gp41) were analyzed by next-generation sequencing for HIV superinfection. HIV superinfection was established if the follow-up sample contained a new, phylogenetically distinct viral population. HIV superinfection and transmission risk were examined by multiple logistic regression, adjusted for Post-Exposure Prophylaxis of Infants study arm, baseline viral load, baseline CD4 cell count, time to resumption of sex, and breastfeeding duration.

RESULTS

Transmitters had lower baseline CD4 cell counts (P = 0.001) and higher viral loads (P < 0.0001) compared with nontransmitters. There were five cases of superinfection among transmitters (rate of superinfection = 4.7/100 person-years) compared with five cases among the nontransmitters (rate of superinfection = 4.4/100 person-years; P = 0.78). HIV superinfection was not associated with increased risk of postnatal MTCT of HIV after controlling for maternal age, baseline viral load, and CD4 cell count (adjusted odds ratio = 2.32, P = 0.30). Longer breastfeeding duration was independently associated with a lower risk of HIV superinfection after controlling for study arm and baseline viral load (P = 0.05).

CONCLUSION

There was a significant level of HIV superinfection in women postpartum, but this was not associated with an increased risk of MTCT via breastfeeding.

Predictors of unstructured antiretroviral treatment interruption and resumption among HIV-positive individuals in Canada

OBJECTIVES

Sustained optimal use of combination antiretroviral therapy (cART) has been shown to decrease morbidity, mortality and HIV transmission. However, incomplete adherence and treatment interruption (TI) remain challenges to the full realization of the promise of cART. We estimated trends and predictors of treatment interruption and resumption among individuals in the Canadian Observational Cohort (CANOC) collaboration.

METHODS

cART-naïve individuals ≥ 18 years of age who initiated cART between 2000 and 2011 were included in the study. We defined TIs as ≥ 90 consecutive days off cART. We used descriptive analyses to study TI trends over time and Cox regression to identify factors predicting time to first TI and time to treatment resumption after a first TI.

RESULTS

A total of 7633 participants were eligible for inclusion in the study, of whom 1860 (24.5%) experienced a TI. The prevalence of TI in the first calendar year of cART decreased by half over the study period. Our analyses highlighted a higher risk of TI among women [adjusted hazard ratio (aHR) 1.59; 95% confidence interval (CI) 1.33-1.92], younger individuals (aHR 1.27; 95% CI 1.15-1.37 per decade increase), earlier treatment initiators (CD4 count ≥ 350 vs. <200 cells/μL: aHR 1.46; 95% CI 1.17-1.81), Aboriginal participants (aHR 1.67; 95% CI 1.27-2.20), injecting drug users (aHR 1.43; 95% CI 1.09-1.89) and users of zidovudine vs. tenofovir in the initial cART regimen (aHR 2.47; 95% CI 1.92-3.20). Conversely, factors predicting treatment resumption were male sex, older age, and a CD4 cell count <200 cells/μL at cART initiation.

CONCLUSIONS

Despite significant improvements in cART since its advent, our results demonstrate that TIs remain relatively prevalent. Strategies to support continuous HIV treatment are needed to maximize the benefits of cART.

Effects of early versus delayed initiation of antiretroviral treatment on clinical outcomes of HIV-1 infection: results from the phase 3 HPTN 052 randomised controlled trial

BACKGROUND

Use of antiretroviral treatment for HIV-1 infection has decreased AIDS-related morbidity and mortality and prevents sexual transmission of HIV-1. However, the best time to initiate antiretroviral treatment to reduce progression of HIV-1 infection or non-AIDS clinical events is unknown. We reported previously that early antiretroviral treatment reduced HIV-1 transmission by 96%. We aimed to compare the effects of early and delayed initiation of antiretroviral treatment on clinical outcomes.

METHODS

The HPTN 052 trial is a randomised controlled trial done at 13 sites in nine countries. We enrolled HIV-1-serodiscordant couples to the study and randomly allocated them to either early or delayed antiretroviral treatment by use of permuted block randomisation, stratified by site. Random assignment was unblinded. The HIV-1-infected member of every couple initiated antiretroviral treatment either on entry into the study (early treatment group) or after a decline in CD4 count or with onset of an AIDS-related illness (delayed treatment group). Primary events were AIDS clinical events (WHO stage 4 HIV-1 disease, tuberculosis, and severe bacterial infections) and the following serious medical conditions unrelated to AIDS: serious cardiovascular or vascular disease, serious liver disease, end-stage renal disease, new-onset diabetes mellitus, and non-AIDS malignant disease. Analysis was by intention-to-treat. This trial is registered with ClinicalTrials.gov, number NCT00074581.

FINDINGS

1763 people with HIV-1 infection and a serodiscordant partner were enrolled in the study; 886 were assigned early antiretroviral treatment and 877 to the delayed treatment group (two individuals were excluded from this group after randomisation). Median CD4 counts at randomisation were 442 (IQR 373-522) cells per μL in patients assigned to the early treatment group and 428 (357-522) cells per μL in those allocated delayed antiretroviral treatment. In the delayed group, antiretroviral treatment was initiated at a median CD4 count of 230 (IQR 197-249) cells per μL. Primary clinical events were reported in 57 individuals assigned to early treatment initiation versus 77 people allocated to delayed antiretroviral treatment (hazard ratio 0·73, 95% CI 0·52-1·03; p=0·074). New-onset AIDS events were recorded in 40 participants assigned to early antiretroviral treatment versus 61 allocated delayed initiation (0·64, 0·43-0·96; p=0·031), tuberculosis developed in 17 versus 34 patients, respectively (0·49, 0·28-0·89, p=0·018), and primary non-AIDS events were rare (12 in the early group vs nine with delayed treatment). In total, 498 primary and secondary outcomes occurred in the early treatment group (incidence 24·9 per 100 person-years, 95% CI 22·5-27·5) versus 585 in the delayed treatment group (29·2 per 100 person-years, 26·5-32·1; p=0·025). 26 people died, 11 who were allocated to early antiretroviral treatment and 15 who were assigned to the delayed treatment group.

INTERPRETATION

Early initiation of antiretroviral treatment delayed the time to AIDS events and decreased the incidence of primary and secondary outcomes. The clinical benefits recorded, combined with the striking reduction in HIV-1 transmission risk previously reported, provides strong support for earlier initiation of antiretroviral treatment.

FUNDING

US National Institute of Allergy and Infectious Diseases.

Haematological changes in African children who received short-term prophylaxis with nevirapine and zidovudine at birth

We assessed the safety of short-term antiretroviral prophylaxis to prevent mother-to-child transmission (MTCT) of HIV by monitoring haematological changes in children up to the age of 18 months. Babies of HIV-infected women were randomised at birth to receive a single dose of nevirapine (NVP) alone or with zidovudine (ZDV) twice daily for a week. Based on the time of presentation to the labour ward, mothers of these babies might or might not have received intrapartum NVP. Complete blood counts were performed at birth and at 1.5, 3, 6, 9, 12, 15 and 18 months. Babies' HIV status was determined by HIV-1 RNA testing. A total of 1755 babies were included in the study. Age-specific mean haemoglobin levels and prevalence of anaemia (haemoglobin < 10 g/dL) were not significantly different in cases where only the babies received a single dose of NVP and cases where NVP was given to mother/infant pairs or additional ZDV to the baby. Among HIV-infected children compared with uninfected children, the age-specific frequency of anaemia was significantly greater, anaemia started earlier and recovery to normal levels was slower and prolonged. A reversible granulocytopenia was observed in all children between 1.5 and 3 months of age. HIV infection significantly increased the children's risk of death. Antiretroviral prophylaxis appeared to protect against anaemia and child death. Short regimens of antiretrovirals to prevent MTCT of HIV are not associated with long-term adverse haematological changes.

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.

Child mortality levels and trends by HIV status in Blantyre, Malawi: 1989-2009

INTRODUCTION

Continuous evaluation of child survival is needed in sub-Saharan Africa where HIV prevalence among women of reproductive age continues to be high. We examined mortality levels and trends over a period of ∼20 years among HIV-unexposed and -exposed children in Blantyre, Malawi.

METHODS

Data from 5 prospective cohort studies conducted at a single research site from 1989 to 2009 were analyzed. In these studies, children born to HIV-infected and -uninfected mothers were enrolled at birth and followed longitudinally for at least 2 years. Information on sociodemographic, HIV infection status, survival, and associated risk factors was collected in all studies. Mortality rates were estimated using birth-cohort analyses stratified by maternal and infant HIV status. Multivariate Cox regression models were used to determine risk factors associated with mortality.

RESULTS

The analysis included 8286 children. From 1989 to 1995, overall mortality rates (per 100 person-years) in these clinic-based cohorts remained comparable among HIV-uninfected children born to HIV-uninfected mothers (range 3.3-6.9) or to HIV-infected mothers (range 2.5-7.5). From 1989 to 2009, overall mortality remained high among all children born to HIV-infected mothers (range 6.3-19.3) and among children who themselves became infected (range 15.6-57.4, 1994-2009). Only lower birth weight was consistently and significantly (P < 0.05) associated with higher child mortality.

CONCLUSIONS

HIV infection among mothers and children contributed to high levels of child mortality in the African setting in the pretreatment era. In addition to services that prevent mother-to-child transmission of HIV, other programs are needed to improve child survival by lowering HIV-unrelated mortality through innovative interventions that strengthen health infrastructure.

Pooled individual data analysis of 5 randomized trials of infant nevirapine prophylaxis to prevent breast-milk HIV-1 transmission

BACKGROUND

In resource-limited settings, mothers infected with human immunodeficiency virus type 1 (HIV-1) face a difficult choice: breastfeed their infants but risk transmitting HIV-1 or not breastfeed their infants and risk the infants dying of other infectious diseases or malnutrition. Recent results from observational studies and randomized clinical trials indicate daily administration of nevirapine to the infant can prevent breast-milk HIV-1 transmission.

METHODS

Data from 5396 mother-infant pairs who participated in 5 randomized trials where the infant was HIV-1 negative at birth were pooled to estimate the efficacy of infant nevirapine prophylaxis to prevent breast-milk HIV-1 transmission. Four daily regimens were compared: nevirapine for 6 weeks, 14 weeks, or 28 weeks, or nevirapine plus zidovudine for 14 weeks.

RESULTS

The estimated 28-week risk of HIV-1 transmission was 5.8% (95% confidence interval [CI], 4.3%-7.9%) for the 6-week nevirapine regimen, 3.7% (95% CI, 2.5%-5.4%) for the 14-week nevirapine regimen, 4.8% (95% CI, 3.5%-6.7%) for the 14-week nevirapine plus zidovudine regimen, and 1.8% (95% CI, 1.0%-3.1%) for the 28-week nevirapine regimen (log-rank test for trend, P < .001). Cox regression models with nevirapine as a time-varying covariate, stratified by trial site and adjusted for maternal CD4 cell count and infant birth weight, indicated that nevirapine reduces the rate of HIV-1 infection by 71% (95% CI, 58%-80%; P < .001) and reduces the rate of HIV infection or death by 58% (95% CI, 45%-69%; P < .001).

CONCLUSIONS

Extended prophylaxis with nevirapine or with nevirapine and zidovudine significantly reduces postnatal HIV-1 infection. Longer duration of prophylaxis results in a greater reduction in the risk of infection.

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.

Prevention of HIV-1 infection with early antiretroviral therapy

BACKGROUND

Antiretroviral therapy that reduces viral replication could limit the transmission of human immunodeficiency virus type 1 (HIV-1) in serodiscordant couples.

METHODS

In nine countries, we enrolled 1763 couples in which one partner was HIV-1-positive and the other was HIV-1-negative; 54% of the subjects were from Africa, and 50% of infected partners were men. HIV-1-infected subjects with CD4 counts between 350 and 550 cells per cubic millimeter were randomly assigned in a 1:1 ratio to receive antiretroviral therapy either immediately (early therapy) or after a decline in the CD4 count or the onset of HIV-1-related symptoms (delayed therapy). The primary prevention end point was linked HIV-1 transmission in HIV-1-negative partners. The primary clinical end point was the earliest occurrence of pulmonary tuberculosis, severe bacterial infection, a World Health Organization stage 4 event, or death.

RESULTS

As of February 21, 2011, a total of 39 HIV-1 transmissions were observed (incidence rate, 1.2 per 100 person-years; 95% confidence interval [CI], 0.9 to 1.7); of these, 28 were virologically linked to the infected partner (incidence rate, 0.9 per 100 person-years, 95% CI, 0.6 to 1.3). Of the 28 linked transmissions, only 1 occurred in the early-therapy group (hazard ratio, 0.04; 95% CI, 0.01 to 0.27; P<0.001). Subjects receiving early therapy had fewer treatment end points (hazard ratio, 0.59; 95% CI, 0.40 to 0.88; P=0.01).

CONCLUSIONS

The early initiation of antiretroviral therapy reduced rates of sexual transmission of HIV-1 and clinical events, indicating both personal and public health benefits from such therapy. (Funded by the National Institute of Allergy and Infectious Diseases and others; HPTN 052 ClinicalTrials.gov number, NCT00074581.).

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.

Resumption of sexual activity and regular menses after childbirth among women infected with HIV in Malawi

OBJECTIVE

To determine the factors associated with resumption of sexual activity and regular menses after childbirth among women infected with HIV-1.

METHODS

Information on sociodemographic, behavioral, and clinical factors was obtained from 2 HIV perinatal studies (NVAZ and PEPI trials) conducted in Malawi, 2000-2009. Factors associated with resumption of sexual activity and menses were analyzed using Cox proportional hazard models.

RESULTS

A total of 1838 women from the NVAZ study and 2982 women from the PEPI study were included in the analysis. Resumption of sexual activity was primarily associated with sociodemographic factors (e.g. in the PEPI study, marital status [adjusted hazard ratio (aHR) 0.56, P<0.001], use of contraceptive method [aHR 8.0, P<0.001], and breastfeeding [aHR 0.52, P<0.001]), whereas resumption of regular menses in the PEPI study was primarily associated with biological factors (e.g. plasma viral load [aHR 0.89, P<0.006], and breastfeeding [aHR 0.23, P<0.001).

CONCLUSION

HIV-infected women need adequate counseling to take into account their HIV infection status before resuming sexual activity after childbirth.

Hypertension in pregnancy among HIV-infected women in sub-Saharan Africa: prevalence and infant outcomes

This analysis was performed to determine the prevalence of hypertension and association of MAP (mean arterial pressure) with birth outcomes among HIV-infected pregnant women not taking antiretrovirals. HIV-infected pregnant women, enrolled into the HPTN024 trial in Tanzania, Malawi and Zambia were followed up at 26-30, 36 weeks, and delivery. The prevalence of hypertension was <1% at both 20-24 weeks and 26-30 weeks and 1.7% by 36 weeks. A 5 mm Hg elevation in MAP increased the risk of stillbirth at 20-24 weeks by 29% (p = 0.001), 32% (p = 0.001) at 26-30 weeks and of low birth weight (LBW) at 36 weeks by 26% (p = 0.001). MAP was not associated with stillbirth at 36 weeks, LBW prior to 36 weeks, preterm birth, neonatal mortality or the risk of maternal to child transmission (MTCT) of HIV.

Effect of prenatal and perinatal antibiotics on maternal health in Malawi, Tanzania, and Zambia

OBJECTIVE

We assessed the effect of prenatal and peripartum antibiotics on maternal morbidity and mortality among HIV-infected and uninfected women.

METHODS

A multicenter trial was conducted at clinical sites in 4 Sub-Saharan African cities: Blantyre and Lilongwe, Malawi; Dar es Salaam, Tanzania; and Lusaka, Zambia. A total of 1558 HIV-infected and 271 uninfected pregnant women who were eligible to receive both the prenatal and peripartum antibiotic/placebo regimens were enrolled. Pregnant women were interviewed at 20-24 weeks of gestation and a physical examination was performed. Women were randomized to receive either antibiotics or placebo. At the 26-30 week visit, participants were given antibiotics or placebo to be taken every 4 hours beginning at the onset of labor and continuing after delivery 3 times a day until a 1-week course was completed. Logistic regression and Cox proportional hazards models were used.

RESULTS

There were no significant differences between the antibiotic and placebo groups for medical conditions, obstetric complications, physical examination findings, puerperal sepsis, and death in either the HIV-infected or the uninfected cohort.

CONCLUSION

Administration of study antibiotics during pregnancy had no effect on maternal morbidity and mortality among HIV-infected and uninfected pregnant women.

Intrapartum antibiotic exposure and early neonatal, morbidity, and mortality in Africa

BACKGROUND

Infants born to women who receive intrapartum antibiotics may have higher rates of infectious morbidity and mortality than unexposed infants.

OBJECTIVE

Our goal was to determine the association of maternal intrapartum antibiotics and early neonatal morbidity and mortality.

METHODS

We performed secondary analysis of data from a multisite randomized, placebo-controlled clinical trial of antibiotics to prevent chorioamnionitis-associated mother-to-child transmission of HIV-1 and preterm birth in sub-Saharan Africa. Early neonatal morbidity and mortality were analyzed. In an intention-to-treat (ITT) analysis, infants born to women randomly assigned to antibiotics or placebo were compared. In addition, non-ITT analysis was performed because some women received nonstudy antibiotics for various clinical indications.

RESULTS

Overall, 2659 pregnant women were randomly assigned. Of these, 2466 HIV-1-infected and HIV-1-uninfected women delivered 2413 live born and 84 stillborn infants. In the ITT analysis, there were no significant associations between exposure to antibiotics and early neonatal outcomes. Non-ITT analyses showed more illness at birth (11.2% vs 8.6%, P = .03) and more admissions to the special care infant unit (12.6% vs 9.8%, P = .04) among infants exposed to maternal intrapartum antibiotics than among unexposed infants. Additional analyses revealed greater early neonatal morbidity and mortality among infants of mothers who received nonstudy antibiotics than of mothers who received study antibiotics.

CONCLUSIONS

There is no association between intrapartum exposure to antibiotics and early neonatal morbidity or mortality. The associations observed in non-ITT analyses are most likely the result of women with peripartum illnesses being more likely to receive nonstudy antibiotics.

Fertility intentions of HIV-1 infected and uninfected women in Malawi: a longitudinal study

This study aimed to determine changes in fertility intentions of HIV-1 infected and uninfected reproductive age women in Blantyre, Malawi. Participants were asked about their fertility intentions at baseline and at 3-month visits for 1 year. Time-to-event statistical models were used to determine factors associated with changes in fertility intentions. Overall, 842 HIV uninfected and 844 HIV infected women were enrolled. The hazard of changing from wanting no more children at baseline to wanting more children at follow-up was 61% lower among HIV infected women compared to HIV uninfected women (P < 0.01) after adjusting for other factors, while HIV infected women were approximately 3 times more likely to change to wanting no more children. The overall pregnancy rate after 12 months was 14.9 per 100 person-years and did not differ among 102 HIV uninfected and 100 infected women who became pregnant. HIV infection is a significant predictor of fertility intentions over time.

Placental malaria and mother-to-child transmission of human immunodeficiency virus-1

There are few studies of the association between placental malaria (PM) and mother-to-child transmission (MTCT) of human immunodeficiency virus-1 (HIV-1), and the results of published studies are inconsistent. To determine the association between PM and MTCT of HIV-1, we performed a secondary analysis of data from a clinical trial of antibiotics to reduce chorioamnionitis. Data regarding 1,662 HIV-1-infected women with live born singleton and first-born twin infants with information regarding PM and infant HIV-1 infection status at birth were analyzed. At the time of the study, women did not have access to antiretroviral drugs for treatment of acquired immunodeficiency syndrome but had received nevirapine prophylaxis to reduce the risk of MTCT of HIV-1. Placental malaria was not associated with the infant HIV-1 infection status at birth (P = 0.67). Adjustment for maternal plasma viral load and CD4+ cell count did not change these results (odds ratio = 1.06, 95% confidence interval = 0.51-2.20, P = 0.87). Placental malaria was more likely to be related to HIV-1 infection at birth among women with low viral load at baseline (P for interaction = 0.08). In conclusion, PM was not associated with infant HIV-1 infection status at birth. The interaction of maternal plasma viral load, PM, and MTCT of HIV-1 warrants further studies.

Genital tract infections among HIV-infected pregnant women in Malawi, Tanzania and Zambia

SUMMARY

The aim of this study was to compare the prevalence and factors associated with genital tract infections among HIV-infected pregnant women from African sites. Participants were recruited from Blantyre and Lilongwe, Malawi; Dar es Salaam, Tanzania; and Lusaka, Zambia. Genital tract infections were assessed at baseline. Of 2627 eligible women enrolled, 2292 were HIV-infected. Of these, 47.8% had bacterial vaginosis (BV), 22.4% had vaginal candidiasis, 18.8% had trichomoniasis, 8.5% had genital warts, 2.6% had chlamydia infection, 2.2% had genital ulcers and 1.7% had gonorrhoea. The main factors associated with genital tract infections included genital warts (adjusted odds ratio [AOR] 1.8, 95% CI 1.2-2.7), genital ulcers (AOR 2.4, 95% CI 1.2-5.1) and abnormal vaginal discharge (AOR 2.5, 95% CI 1.9-3.3) for trichomoniasis. BV was the most common genital tract infection followed by candidiasis and trichomoniasis. Differences in burdens and risk factors call for enhanced interventions for identification of genital tract infections among HIV-infected women.

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.)

Natural history and risk factors associated with early and established HIV type 1 infection among reproductive-age women in Malawi

BACKGROUND

Data evaluating the biological events and determinants of early human immunodeficiency virus type 1 (HIV-1) infection are limited in sub-Saharan Africa. We examined plasma viral levels and trends during early and established HIV-1 infection among reproductive-age women who participated in a randomized trial to treat genital tract infection in Malawi. We also assessed the association of injectable hormonal contraceptive use with HIV-1 infection.

METHODS

We studied 3 groups of women who were infected or uninfected with HIV-1: seroconverters, seroprevalent women, and seronegative women. Questionnaires and blood samples were collected at baseline and every 3 months for 1 year. The virus set point in seroconverters and levels and trends of viral load over time were determined. The associations of injectable hormonal contraceptive use with HIV-1 infection and viral load were assessed using conditional logistic regression and mixed-effect models, respectively.

RESULTS

In the original clinical trial, 844 women infected with HIV-1 and 842 women not infected with HIV-1 were enrolled. Of 31 women who experienced seroconversion during 12 months, 27 were matched with 54 seroprevalent and 54 seronegative women. The estimated median plasma virus set point was 4.45 log(10) copies/mL (interquartile range, 4.32-5.14 log(10) copies/mL). Injectable hormonal contraceptive use was significantly associated with HIV-1 seroconversion (adjusted odds ratio, 10.42; P = .03) but not with established HIV-1 infection. Among the seroconverters, a statistically significant interaction was found between the linear association of viral load and time of injectable hormonal contraceptive use (regression coefficient, -0.14; P = .02).

CONCLUSION

Knowledge of virus set point and trends of viral load in HIV-1 seroincident and seroprevalent asymptomatic women could assist in antiretroviral treatment management.

Nutritional indicators of adverse pregnancy outcomes and mother-to-child transmission of HIV among HIV-infected women

BACKGROUND

Poor nutrition may be associated with mother-to-child transmission (MTCT) of HIV and other adverse pregnancy outcomes.

OBJECTIVE

The objective was to examine the relation of nutritional indicators with adverse pregnancy outcomes among HIV-infected women in Tanzania, Zambia, and Malawi.

DESIGN

Body mass index (BMI; in kg/m(2)) and hemoglobin concentrations at enrollment and weight change during pregnancy were prospectively related to fetal loss, neonatal death, low birth weight, preterm birth, and MTCT of HIV.

RESULTS

In a multivariate analysis, having a BMI < 21.8 was significantly associated with preterm birth [odds ratio (OR): 1.82; 95% CI: 1.34, 2.46] and low birth weight (OR: 2.09; 95% CI: 1.41, 3.08). A U-shaped relation between weight change during pregnancy and preterm birth was observed. Severe anemia was significantly associated with fetal loss or stillbirth (OR: 3.67; 95% CI: 1.16, 11.66), preterm birth (OR: 2.08; 95% CI: 1.39, 3.10), low birth weight (OR: 1.76; 95% CI: 1.07, 2.90), and MTCT of HIV by the time of birth (OR: 2.26; 95% CI: 1.18, 4.34) and by 4-6 wk among those negative at birth (OR: 2.33; 95% CI: 1.15, 4.73).

CONCLUSIONS

Anemia, poor weight gain during pregnancy, and low BMI in HIV-infected pregnant women are associated with increased risks of adverse infant outcomes and MTCT of HIV. Interventions that reduce the risk of wasting or anemia during pregnancy should be evaluated to determine their possible effect on the incidence of adverse pregnancy outcomes and MTCT of HIV.

The effect of vaginal douching cessation on bacterial vaginosis: a pilot study

OBJECTIVE

The objective of the study was to evaluate the risk for bacterial vaginosis (BV) in a douching cessation trial.

STUDY DESIGN

Thirty-nine reproductive-age women who reported use of douche products were enrolled into a 20-week study consisting of a 4 week douching observation (phase I) followed by 12-weeks of douching cessation (phase II). In phase III, participants then chose to resume douching or continue cessation for the remaining 4 weeks. Self-collected vaginal samples were obtained twice weekly in the first 16 weeks, and 1 sample was collected during week 20 (1107 samples total). BV was diagnosed by Nugent score of 7 or greater. Conditional logistic regression was used to evaluate douching cessation on the risk of BV.

RESULTS

The adjusted odds ratio (aOR) for BV in the douching cessation phase, as compared with the douching-observation phase was 0.76 (95% confidence interval [CI], 0.33 to 1.76). Among women who reported their primary reason for douching was to cleanse after menstruation, BV was significantly reduced in douching cessation (aOR:0.23; 95% CI, 0.12 to 0.44).

CONCLUSION

Vaginal douching cessation may reduce the risk for BV in a subset of women.

Comparison of LigAmp and an ASPCR assay for detection and quantification of K103N-containing HIV variants

We compared the ability of the LigAmp assay and an ASPCR assay to detect and quantify K103N-containing HIV variants in samples from 63 women who received single-dose nevirapine in a clinical trial. Samples were first analyzed with the ViroSeq HIV Genotyping system, and ViroSeq PCR products were used as templates for the LigAmp and ASPCR assays. A cutoff of 0.5% K103N for detection of K103N was used for both assays. Results for the percentage K103N were similar for the two assays (R(2) = 0.92). Forty-six samples (73.0%) were positive for K103N by both assays and 13 samples (20.6%) were negative by both assays. Four samples (6.3%) were positive by ASPCR only. No samples were positive by LigAmp only. Eight discordant samples were analyzed in more detail. Sequence polymorphisms near oligonucleotide binding sites provided a possible explanation for the discordance in four of eight samples. The percentage K103N was also determined by analyzing 40 HIV clones from each of these eight samples, using a combined amplification/sequencing method (AmpliSeq). The percentage K103N determined by clonal analysis was consistent with the LigAmp result for five of eight samples, and was consistent with the ASPCR result for three of eight samples. Among 320 clones analyzed, we identified eight different codons at position 103 (mean = 3.8 codons/sample), which encoded six different amino acids, illustrating the extensive genetic diversity in HIV. Further studies are needed to compare performance of assays for detection and quantification of HIV drug resistance mutations in clinical samples.

HIV Seroreversion Time in HIV-1-Uninfected Children Born to HIV-1-Infected Mothers in Malawi

OBJECTIVE

To study temporal changes in HIV-1 seroreversion (change in reactivity of HIV serology from positive to negative) in uninfected infants born to HIV-1-infected mothers.

METHODS

Secondary analysis of data from 3 cohort studies conducted in Malawi among infants born 1989 through 1991 (International Collaborative AIDS Research [ICAR]), 1993 through 1996 (HIV Network for Prevention Trials [HIVNET]), and 2000 through 2003 (nevirapine/zidovudine [NVAZ]). The proportion of children HIV seroreverting at ages 15, 18, and 21 months and the relative odds for seroreversion comparing infants born before 1997 to those born after 1999 were calculated.

RESULTS

Included in this analysis were 635 infants from ICAR, 459 from HIVNET, and 1020 from NVAZ. During the study, there was a consistent trend of decrease in proportion of children seroreverting over time: highest during 1989 through 1991, intermediate during 1993 through 1996, and lowest during 2000 through 2003. Additionally, there was a strong association between seroreversion and year of birth (before 1997 vs. after 1999): adjusted relative odds 5.1 at 15 months, 8.2 at 18 months, and 11.2 at 21 months.

CONCLUSIONS

Age of seroreversion in HIV-1-exposed uninfected infants increased over time. Persistence of maternal HIV-1 antibodies could have implications on timing of infant HIV-1 diagnosis using serological diagnostic methods.

Human papillomavirus seroprevalence among young male and female drug users

OBJECTIVES

To determine seroprevalence and correlates of exposure to HPV 16, 18, and 53 among 15- to 30-year-old drug users in Baltimore, MD.

STUDY DESIGN

Young, newly initiated injection and noninjection drug users underwent a behavioral risk assessment and HPV serology testing. Sex-specific analyses were performed comparing seropositive and seronegative participants using chi2, Mann-Whitney tests, and logistic regression.

RESULTS

Participants (n = 553) were 43.0% female, 40.2% African American, and median age was 24 years. HPV seroprevalence among females and males, respectively, was: HPV-16, 38.2% and 7.0%; HPV-18, 42.4% and 7.3%; and HPV-53, 27.7% and 5.1%. Correlates of HPV seropositivity among females included being African American and anal sex, and among males, having had sex with another male.

CONCLUSIONS

HPV seroprevalence was high among young drug users and significantly higher among females than males, supporting previous findings. Further research is required to fully understand HPV risk factors among men and the contribution of anal transmission in women.

Micronutrient supplements and mortality of HIV-infected adults with pulmonary TB: a controlled clinical trial

SETTING

Zomba and Blantyre, Malawi, Africa.

OBJECTIVES

To determine whether daily micronutrient supplementation reduces the mortality of human immunodeficiency virus (HIV) infected adults with pulmonary tuberculosis (TB).

DESIGN

A randomised, controlled clinical trial of micronutrient supplementation for HIV-positive and HIV-negative adults with pulmonary TB. Participants were enrolled at the commencement of chemotherapy for sputum smear-positive pulmonary TB and followed up for 24 months.

RESULTS

A total of 829 HIV-positive and 573 HIV-negative adults were enrolled. During follow-up, 328 HIV-positive and 17 HIV-negative participants died. The proportion of HIV-positive participants who died in the micronutrient and placebo groups was 38.7% and 40.4%, respectively (P = 0.49). Micronutrient supplementation did not reduce mortality (hazard ratio [HR] 0.93, 95%CI 0.75-1.15) among HIV-positive adults.

CONCLUSIONS

Micronutrient supplementation at the doses used in this study does not reduce mortality in HIV-positive adults with pulmonary TB in Malawi.

HIV type 1 variants with nevirapine resistance mutations are rarely detected in antiretroviral drug-naive African women with subtypes A, C, and D

K103N is frequently detected in HIV-infected women after single dose (SD) nevirapine (NVP). K103N-containing variants were detected more frequently by the ViroSeq HIV-1 Genotyping System in women with subtype C (69.2%) than subtypes A (19.4%, p < 0.0001) or D (36.1%, p < 0.0001). K103N-containing variants were also detected more frequently and at higher levels in women with subtype C by the LigAmp assay. In this report, we analyzed samples collected prior to or within hours after SD NVP administration from antiretroviral drug-naive African women with subtypes A, C, and D. Only 1/254 samples had an NVP resistance mutation detected with the ViroSeq system, and only 4/236 samples had K103N detected at < 0.5% with the LigAmp assay [2/110 (1.8%) with subtype A, 1/46 (2.2%) with subtype C, and 1/80 (1.3%) with subtype D] (p = 0.92). We did not detect significant differences in the pre-NVP frequency of NVP resistance mutations or the pre-NVP levels of K103N-containing variants in women with subtypes A, C, and D that explain the dramatic subtype-based differences in emergence of HIV-1 variants with these mutations after SD NVP exposure.

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.

Fetal Fibronectin and Adverse Infant Outcomes in a Predominantly Human Immunodeficiency Virus–Infected African Population

OBJECTIVE

To evaluate the relationship between fetal fibronectin and preterm birth and maternal-to-child transmission of human immunodeficiency virus (HIV) in an African population of predominantly HIV-infected women.

METHODS

During a trial of second trimester and intrapartum antibiotics compared with placebo to prevent chorioamnionitis and reduce preterm birth and mother-to-child transmission of HIV, vaginal fluid was collected before antibiotics (20-24 weeks) and after treatment at 28 weeks and assayed for fetal fibronectin. Pregnancy outcomes of 2,353 women delivering liveborn singleton infants are presented.

RESULTS

Positive fetal fibronectin assays (50 ng/mL or more) were detected in 4.2% and 4.9% of samples at 20-24 weeks and 28 weeks. Positive fetal fibronectin assays at 28 weeks but not at 20-24 weeks were associated with lower mean birthweight (199 g, P<.001); lower mean gestational age (2 weeks, P<.001); six-fold higher rate of preterm birth less than 32 weeks (10.8% compared with 1.9%, odds ratio 6.3, 95% confidence interval 3.2-12.3) and a two-fold higher rate of preterm birth less than 37 weeks (38.7 compared with 22.0%, odds ratio 2.3, 95% confidence interval 1.5-3.3). Also, at 28 weeks, as the fetal fibronectin values increased, each of the outcomes worsened, and every test of trend was significant. An association between elevated fetal fibronectin levels and mother-to-child transmission of HIV was present at 20 to 24 weeks but not at 28 weeks. Antibiotic treatment at 20 to 24 weeks was not associated with fetal fibronectin levels at 28 weeks.

CONCLUSION

In a population of predominantly HIV- infected African women, fetal fibronectin concentrations at 28 but not at 20-24 weeks were associated with increased risk of preterm birth. The associations were stronger for early preterm birth and when fetal fibronectin levels were higher. High levels of fetal fibronectin were positively associated with mother-to-child transmission of HIV at 20 -24 but not at 28 weeks. Antibiotic treatment did not influence fetal fibronectin levels.

CLINICAL TRIAL REGISTRATION

www.clinicalTrials.gov, NCT00021671

LEVEL OF EVIDENCE

I.

HPTN 024 study: histologic chorioamnionitis, antibiotics and adverse infant outcomes in a predominantly HIV-1-infected African population

OBJECTIVE

Histologic chorioamnionitis has been associated with preterm birth and low birthweight. Our goal was to evaluate the relationship between polymorphonuclear cell and mononuclear cell placental infiltrations and adverse infant outcomes.

STUDY DESIGN

Data from women who were enrolled in a trial of antibiotics for prevention of mother-to-child transmission of HIV-1 and of preterm birth were analyzed. Women who had HIV and women who did not have HIV were assigned randomly to either metronidazole 250 mg and erythromycin 250 mg at 20 to 24 weeks of gestation 3 times daily for 7 days and metronidazole 250 mg and ampicillin 500 mg every 4 hours during labor or identical placebos. Women with HIV were offered nevirapine at delivery for the prevention of mother-to-child transmission. At delivery, various placental sites were evaluated for polymorphonuclear cell and mononuclear cell infiltration.

RESULTS

Polymorphonuclear and mononuclear cell infiltrations were common in the decidua (18% and 43%, respectively) and chorioamnion (28% and 34%, respectively). Gestational age and birthweight were lower among women with polymorphonuclear cell infiltrations, with these relationships generally stronger at earlier gestational age and birthweight. Mononuclear infiltrations were not associated with adverse outcomes. Neither polymorphonuclear cell nor mononuclear placental infiltrations were associated with mother-to-child transmission of HIV. Antibiotic use was not associated with reduced polymorphonuclear or mononuclear cell infiltrations.

CONCLUSION

Polymorphonuclear cell infiltrations were associated with preterm birth and decreased birthweight and gestational age. Antibiotic use was not associated with reductions in polymorphonuclear or mononuclear cell infiltrations. In this nevirapine-treated population, neither polymorphonuclear nor mononuclear cell infiltration was associated with the mother-to-child transmission of HIV.

Effect of antibiotic treatment of subclinical mastitis on human immunodeficiency virus type 1 RNA in human milk

Although subclinical mastitis is associated with increased HIV load in breast milk, it is not known whether empirical treatment with antibiotics will reduce breast milk HIV load. We examined the effect of antibiotic treatment for subclinical mastitis on HIV load in breast milk. Seventy-five HIV-infected post-partum women in Malawi with subclinical mastitis were treated with oral amoxicillin/clavulanic acid and were followed between 1 and 24 weeks later. Breastmilk HIV-1 load and sodium concentration were measured and microbiological studies were performed at presentation. At 1 week (n = 34), the proportion of women with elevated breast milk leukocyte counts decreased significantly to 41.2% (p < 0.0001) and there was a nonsignificant increase in breast milk HIV-1 RNA load (p = 0.9264) and sodium concentration (p = 0.08) in the affected breast. At 4 to 12 weeks (n = 63), breast milk HIV-1 RNA load and sodium concentration decreased significantly (p < 0.05) and 17.5% had elevated breast milk leukocyte counts. Treatment with amoxicillin/clavulanic acid was associated with a significant decrease in inflammation of the breast, but breast milk HIV load remained elevated despite a significant decrease from baseline. These findings have important implications regarding how mothers should be counselled on safety of resuming breastfeeding after resolution of subclinical mastitis.

Sensitivity of the ViroSeq HIV-1 genotyping system for detection of the K103N resistance mutation in HIV-1 subtypes A, C, and D

The US Food and Drug Administration-cleared ViroSeq HIV-1 Genotyping System (ViroSeq) and other population sequencing-based human immunodeficiency virus type 1 (HIV-1) genotyping methods detect antiretroviral drug resistance mutations present in the major viral population of a test sample. These assays also detect some mutations in viral variants that are present as mixtures. We compared detection of the K103N nevirapine resistance mutation using ViroSeq and a sensitive, quantitative point mutation assay, LigAmp. The LigAmp assay measured the percentage of K103N-containing variants in the viral population (percentage of K103N). We analyzed 305 samples with HIV-1 subtypes A, C, and D collected from African women after nevirapine administration. ViroSeq detected K103N in 100% of samples with >20% K103N, 77.8% of samples with 10 to 20% K103N, 71.4% of samples with 5 to 10% K103N, and 16.9% of samples with 1 to 5% K103N. The sensitivity of ViroSeq for detection of K103N was similar for subtypes A, C, and D. These data indicate that the ViroSeq system reliably detects the K103N mutation at levels above 20% and frequently detects the mutation at lower levels. Further studies are needed to compare the sensitivity of different assays for detection of HIV-1 drug resistance mutations and to determine the clinical relevance of HIV-1 minority variants.

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.

Quantitative analysis of HIV-1 variants with the K103N resistance mutation after single-dose nevirapine in women with HIV-1 subtypes A, C, and D

INTRODUCTION

We used a sensitive point mutation assay, LigAmp, to detect and quantify K103N-containing variants in African women who received single-dose nevirapine (NVP) to prevent mother-to-child HIV-1 transmission.

METHODS

Plasma for testing was collected 6 to 8 weeks postpartum from 301 women (144 subtype A, 63 subtype C, and 94 subtype D).

RESULTS

The portion of women with 0.5% or more K103N-containing variants was lowest for subtype A (60/144, 41.7%) and highest for subtype C (44/63, 69.8%; P < 0.0001). K103N was rarely detected in pre-NVP samples. In a multivariate model, K103N detection was associated with HIV-1 subtype (C > A), after adjusting for log10 delivery viral load, the number of days between NVP dosing and sample collection, age, and parity. Among women with K103N detected: (1) the median %K103N was lower for subtype A (2.2%) than C (11.7%, P = 0.0001) or D (5.5%, P = 0.04), and (2) in a multivariate linear model, higher log10 (%K103N) was associated with HIV subtype (C > A, P = 0.0001; D > A, P = 0.01; and C vs D, no difference), but not other factors.

CONCLUSIONS

After administration of single-dose NVP, K103N was detected more frequently and at higher levels in women with subtypes C and D than A. Further studies are needed to evaluate the clinical significance of NVP-resistant variants in this setting.

A phase III clinical trial of antibiotics to reduce chorioamnionitis-related perinatal HIV-1 transmission

OBJECTIVE

A multisite study was conducted in Africa to assess the efficacy of antibiotics to reduce mother-to-child transmission (MTCT) of HIV-1.

DESIGN

A randomized, double-blinded, placebo-controlled, phase III clinical trial.

METHODS

HIV-1-infected women were randomly assigned at 20-24 weeks' gestation to receive either antibiotics (metronidazole plus erythromycin antenatally and metronidazole plus ampicillin intrapartum) or placebo. Maternal study procedures were performed at 20-24, 26-30, and 36 weeks antenatally, and at labor/delivery. Infants were seen at birth, 4-6 weeks, and 3, 6, 9 and 12 months. The primary efficacy endpoints were overall infant HIV-1 infection and HIV-1-free survival at 4-6 weeks. All women and infants received single-dose nevirapine prophylaxis in this study.

RESULTS

A total of 1510 live-born infants were included in the primary analysis. The proportions of HIV-1-infected infants at birth were similar (antibiotics 7.1%; placebo 8.3%; P = 0.41). Likewise, there were no statistically significant differences at 4-6 weeks in the overall risk of MTCT of HIV-1 (antibiotics 16.2%; placebo 15.8%; P = 0.89) or HIV-1-free survival (79.4% in each study arm). Post-randomization, the proportion of women with bacterial vaginosis at the second antenatal visit was significantly lower in the antibiotics arm compared with the placebo arm (23.8 versus 39.7%; P < 0.001), but the frequency of histological chorioamnionitis was not different (antibiotics 36.9%; placebo 39.7%; P = 0.30). Adverse events in mothers and their infants did not differ by randomization arm.

CONCLUSION

This simple antepartum and peripartum antibiotic regimen did not reduce the risk of MTCT of HIV-1.

Association between the Replication Capacity and Mother‐to‐Child Transmission of HIV‐1, in Antiretroviral Drug–Naive Malawian Women

Replication capacity and transmission of human immunodeficiency virus (HIV)-1 in antiretroviral drug-naive Malawian women who had subtype C infection were investigated. Infant children of these women received either 1 dose of nevirapine or 1 dose of nevirapine plus 1 week of daily doses of zidovudine. PhenoSense HIV was used to determine replication capacity in 49 women whose infants were infected with HIV-1 and in 47 women whose infants were uninfected by 6-8 weeks of age. Mean replication capacity was higher in transmitters than in nontransmitters (P=.01). In a multivariate model, higher replication capacity was associated with transmission (odds ratio, 1.45 for each 10% increase in replication capacity [95% confidence interval, 1.11-1.90]; P = .0063), after adjustment for maternal HIV-1 load and other factors.

Higher In Utero and Perinatal HIV Infection Risk in Girls Than Boys

OBJECTIVE

This study analyzed mother-to-child HIV transmission rates by sex and exposure time for babies born to HIV-infected, untreated African women.

METHODS

Data were analyzed from 2 independent studies done in Malawi during the 1990s. Infections were established by polymerase chain reaction on blood samples. Odds ratios (ORs) for transmission were examined by period at risk: in utero (infected in umbilical cord blood), perinatal (infected in 1st postnatal blood > or =4 weeks), and postnatal (later postnatal infection).

RESULTS

Among 1394 singleton births, girls were more likely to become infected than boys. For in utero transmission, the OR was 1.4 (95% CI: 0.9 to 2.2). For transmission during early life (umbilical cord blood not available) the OR was 2.7 (95% CI: 1.5 to 4.9). However, transmission risks in the perinatal and postnatal infection periods did not differ in boys and girls. Among 303 tested twin-birth pairs, girls were at higher risk than boys for in utero (OR: 2.6; 95% CI: 1.2 to 5.8) and perinatal (OR: 1.9; 95% CI: 1.0 to 3.7) infection. Recognized mother-to-child transmission risk factors did not explain the higher risk of infection in girls.

CONCLUSIONS

Girls were at higher risk of early (in utero and perinatal) HIV infection than boys. It is proposed that minor histocompatibility reactions between maternal lymphocytes and infant Y chromosome-derived antigens reduce the risk of HIV transmission in boys.

The HPTN 024 Study: the efficacy of antibiotics to prevent chorioamnionitis and preterm birth

OBJECTIVE

The use of antibiotics to prevent preterm birth has achieved mixed results. Our goal in this study was to determine if antibiotics given prenatally and during labor reduce the incidence of preterm birth and histologic chorioamnionitis.

STUDY DESIGN

A double-blind randomized placebo-controlled trial of antibiotics to reduce preterm birth was conducted in 4 African sites. Both HIV-infected and uninfected pregnant women were given 2 courses of antibiotics, prenatally at 24 weeks (metronidazole 250 mg and erythromycin 250 mg tid orally for 7 days), and during labor (metronidazole 250 mg and ampicillin 500 mg q 4 hours) or identically appearing placebos. Two thousand ninety-eight HIV-infected and 335 HIV-uninfected women had evaluable end points, including gestational age determined by both obstetric and pediatric criteria and birth weight (BWT). Pre- and post-treatment rates of various sexually transmitted infections (STI) were determined and placentas were evaluated for histologic chorioamnionitis.

RESULTS

Comparing antibiotic versus placebo treated HIV-infected and uninfected women, there were few differences in mean gestational age at delivery, the percent of preterm births, the time between randomization and delivery, or BWT. Four weeks after the 24-week antibiotic/placebo course, bacterial vaginosis, and trichomoniasis were reduced by 49% to 61% in the antibiotic groups compared with the placebo groups. However, in both the HIV-infected and uninfected groups, the placentas showed no difference in the rate of histologic chorioamnionitis. There were significant differences between HIV-infected and uninfected women, with the former having less education, a history of more stillbirths, more STIs, and in this pregnancy, a lower BWT (2949 vs 3100 g, P < .0001).

CONCLUSION

Despite reducing the rate of vaginal infections, the antibiotic regimen used in this study did not reduce the rate of preterm birth, increase the time to delivery, or increase BWT. Failure of this regimen to reduce the rate of histologic chorioamnionitis may explain the reason the antibiotics failed to reduce preterm birth.

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.

Status of carotenoids, vitamin A, and vitamin E in the mother-infant dyad and anthropometric status of infants in Malawi

This prospective study was carried out during February 2000-April 2003 to characterize the relationship between the status of carotenoids, vitamin E, and retinol and anthropometric status in apparently healthy infants and their mothers in Blantyre, Malawi. Anthropometric status of infants and concentrations of carotenoids (alpha-carotene, beta-carotene, beta-cryptoxanthin, lutein, zeaxanthin, and lycopene), retinol, and alpha-tocopherol in plasma were measured in 173 infants at 12 months of age, and concentrations of carotenoids, retinol, and a-tocopherol in plasma were measured in their mothers two weeks postpartum. In multivariate analyses, concentrations of retinol, total carotenoids, non-provitamin A carotenoids, and alpha-tocopherol in infants were associated with under-weight (p = 0.05). Concentrations of a-tocopherol were associated with wasting (p = 0.04). Concentrations in mothers and infants were all correlated (correlation coefficients from 0.230 to 0.502, p < 0.003). The findings suggest that poor status of carotenoids, retinol, and alpha-tocopherol in infants is associated with their poor anthropometric status, and status of carotenoids, retinol, and alpha-tocopherol in mothers and infants has a low-to-moderate association in the mother-infant dyad.