Maternal and Breastmilk Viral Load: Impacts of Adherence on Peripartum HIV Infections Averted-The Breastfeeding, Antiretrovirals, and Nutrition Study.

Background: Antiretroviral (ARV) interventions are used to reduce HIV viral replication and prevent mother-to-child transmission. Viral suppression relies on adherence to ARVs.

Methods: A 2-phase study was conducted using data from the Breastfeeding, Antiretrovirals, and Nutrition study.

Frequent nevirapine resistance in infants infected by HIV-1 via breastfeeding while on nevirapine prophylaxis.

Objective: The objective of this study is to assess nevirapine (NVP) resistance in infants who became infected in the three arms of the Breastfeeding, Antiretrovirals and Nutrition (BAN) study: daily infant NVP prophylaxis, triple maternal antiretrovirals or no extra intervention for 28 weeks of breastfeeding.

Design: A prospective cohort study.

Methods: The latest available plasma or dried blood spot specimen was tested from infants who became HIV-positive between 3 and 48 weeks of age.

Hepatitis B virus infection among HIV-infected pregnant women in Malawi and transmission to infants.

Background & Aims: The extent of HBV infection to infants of HBV/HIV-coinfected pregnant women in sub-Saharan Africa is unknown. The aim of this study was to assess prevalence of HBV infection among antiretroviral-naïve, HIV-infected pregnant women in Malawi and examine HBV transmission to their infants.

Methods: Plasma from 2048 HIV-infected, Malawian women and their infants were tested for markers of HBV infection.

Prevalence of hepatitis C virus infection among human immunodeficiency virus-1-infected pregnant women in Malawi: the BAN study.

Background: In Sub-Saharan Africa, prevalence estimates of hepatitis C virus (HCV) vary widely.

Objectives: To assess the prevalence of HCV infection among HIV-infected, pregnant women screened for a large clinical trial in Lilongwe, Malawi.

Study Design: Plasma from 2041 HIV-infected, pregnant women was screened for anti-HCV IgG using a chemiluminiscent immunometric assay (CIA).

Common human genetic variants and HIV-1 susceptibility: a genome-wide survey in a homogeneous African population.

Objective: To date, CCR5 variants remain the only human genetic factors to be confirmed to impact HIV-1 acquisition. However, protective CCR5 variants are largely absent in African populations, in which sporadic resistance to HIV-1 infection is still unexplained. We investigated whether common genetic variants associate with HIV-1 susceptibility in Africans.

CD16+ monocyte subset preferentially harbors HIV-1 and is expanded in pregnant Malawian women with Plasmodium falciparum malaria and HIV-1 infection.

In a cross-sectional study, monocyte subsets in placental, cord, and maternal peripheral blood from pregnant Malawian women with human immunodeficiency virus (HIV)-1 infection and/or malaria were analyzed. HIV-uninfected Malawian women had higher baseline proportions of CD16(+) monocytes than those reported for healthy adults in developed countries. Malaria was associated with an increase in the proportion of CD16(+) monocytes that was significant in women coinfected with HIV-1.

Maternal syphilis infection is associated with increased risk of mother-to-child transmission of HIV in Malawi.

Objective: To determine the association between maternal syphilis and HIV mother-to-child transmission (MTCT).

Design: Prospective cohort study.

Methods: Pregnant women admitted at Queen Elizabeth Central Hospital (Malawi) in late third trimester were screened for HIV (by HIV rapid tests) and syphilis (by rapid plasma regain test and Treponema pallidum hemagglutination assay).

Mutations associated with sulfadoxine-pyrimethamine and chlorproguanil resistance in Plasmodium falciparum isolates from Blantyre, Malawi.

We conducted a prevalence study of mutations in Plasmodium falciparum that are associated with antifolate resistance in Blantyre, Malawi. The dihydrofolate reductase 164-Leu mutation, which confers resistance to both pyrimethamine and chlorproguanil, was found in 4.7% of the samples.

Malaria during pregnancy and foetal haematological status in Blantyre, Malawi.

Background: Although maternal anaemia often stems from malaria infection during pregnancy, its effects on foetal haemoglobin levels are not straightforward. Lower-than-expected cord haemoglobin values in malarious versus non-malarious regions were noted by one review, which hypothesized they resulted from foetal immune activation to maternal malaria. This study addressed this idea by examining cord haemoglobin levels in relation to maternal malaria, anaemia, and markers of foetal immune activation.

Measuring allelic heterogeneity in Plasmodium falciparum by a heteroduplex tracking assay.

We developed a novel Plasmodium falciparum genotyping strategy based on the heteroduplex tracking assay (HTA) method commonly used to genotype viruses. Because it can detect both sequence and size polymorphisms, we hypothesized that HTA is more sensitive than current methods. To test this hypothesis, we compared the ability of HTA and a nested polymerase chain reaction (PCR) to detect genetic diversity in 17 Thai samples.

Prevalence of pfcrt mutations in Congolese and Malawian Plasmodium falciparum isolates as determined by a new Taqman assay.

A real-time PCR assay was developed to detect the K76T point mutation in the Plasmodium falciparum putative chloroquine resistance transporter gene. The assay was used with malaria positive clinical isolates from Rutshuru in the eastern part of the Democratic Republic of the Congo (DRC) and from Malawi. The K76T mutation was found in 52/56 (93%) clinical isolates from the DRC, where chloroquine resistance is high, but in none of the 12 isolates tested from Malawi where chloroquine is now rarely used.

Risk factors and mechanisms of preterm delivery in Malawi.

Problem: We examined risk factors and mechanisms of preterm delivery (PTD) in malaria-exposed pregnant women in Blantyre, Malawi.

Method Of Study: The human immunodeficiency virus (HIV), malaria, syphilis, and anemia were assessed in a cross-sectional study of 572 pregnant women. In a nested case-control study, chorioamnionitis (CAM) was examined; tumor necrosis factor (TNF)-alpha, interleukin (IL)-6, IL-8, macrophage inflammatory protein (MIP)-1alpha, monocyte chemotactic protein (MCP)-1, transforming growth factor (TGF)-beta, cortisol, and corticotropin-releasing hormone were measured in placental, maternal and/or cord blood.

The effect of Plasmodium falciparum malaria on peripheral and placental HIV-1 RNA concentrations in pregnant Malawian women.

Objective: To investigate the effect of placental Plasmodium falciparum malaria infection on peripheral and/or placental HIV-1 viral load.

Design: A cross-sectional study of HIV-infected pregnant women, with and without placental malaria, delivering at Queen Elizabeth Central Hospital in Malawi.

Methods: Peripheral blood samples were collected from consenting women and tested for HIV.

Plasmodium falciparum: PCR detection and genotyping of isolates from peripheral, placental, and cord blood of pregnant Malawian women and their infants.

Polymerase chain reaction (PCR) is both a sensitive means of detecting malaria parasitaemia, and a simple tool for identifying genetic differences in parasites infecting human subjects. We compared PCR to microscopy in detection of Plasmodium falciparum infection in peripheral, placental and cord blood samples collected from 131 pregnant Malawian women and their infants in 1997-99. Infections detected by species-specific PCR were genotyped at the merozoite surface protein 1 and 2 loci, and minimum numbers of infecting genotypes determined.

Molecular markers for failure of sulfadoxine-pyrimethamine and chlorproguanil-dapsone treatment of Plasmodium falciparum malaria.

Molecular assays for monitoring sulfadoxine-pyrimethamine-resistant Plasmodium falciparum have not been implemented because of the genetic and statistical complexity of the parasite mutations that confer resistance and their relation to treatment outcomes. This study analyzed pretreatment dihydrofolate reductase (DHFR) and dihydropteroate synthase (DHPS) genotypes and treatment outcomes in a double-blind, placebo-controlled trial of sulfadoxine-pyrimethamine and chlorproguanil-dapsone treatment for uncomplicated P. falciparum malaria.