Mother‐to‐child transmission of HIV‐1: association with malaria prevention, anaemia and placental malaria^*

Abstract

Malaria infection may impact on mother-to-child transmission (MTCT) of HIV-1. Prevention of malaria in pregnancy could thus potentially affect MTCT of HIV. We studied the impact of intermittent preventive treatment during pregnancy (IPTp) on HIV-1 MTCT in southern Mozambique. MethodsA total of 207 HIV-positive Mozambican pregnant women were enrolled in the study as part of a randomized placebo-controlled trial of two-dose sulfadoxine-pyrimethamine (SP) IPTp in women receiving single-dose nevirapine to prevent MTCT of HIV. HIV RNA viral load, maternal anaemia and peripheral and placental malaria were assessed at delivery. Infant HIV status was determined by DNA polymerase chain reaction (PCR) at 1 month of age. ResultsThere were 19 transmissions of HIV in 153 mother-infant pairs. IPTp with SP did not have a significant impact on MTCT (11.8% in the SP group vs. 13.2% in the placebo group; P 5 0.784) or on maternal HIV RNA viral load [16 312 (interquartile range {IQR} 4076-69 296) HIV-1 RNA copies/mL in the SP group vs. 18 274 (IQR 5471-74 104) copies/mL in the placebo group; P 5 0.715]. In multivariate analysis, maternal HIV RNA viral load [adjusted odds ratio (AOR) 19.9; 95% confidence interval (CI) 2.3-172; P 5 0.006] and anaemia (haematocrit o33%; AOR 7.5; 95% CI 1.7-32.4; P 5 0.007) were independent risk factors for MTCT. Placental malaria was associated with a decrease in MTCT (AOR 0.23; 95% CI 0.06-0.89; P 5 0.034). ConclusionsIPTp with SP was not associated with a significant impact on MTCT of HIV. Maternal anaemia was an independent risk factor for MTCT.Keywords: anaemia, intermittent preventive treatment, mother-to-child transmission, placental malaria, pregnancy Received: 18 February 2008, accepted 15 May 2008 Introduction HIV/AIDS and malaria infections are two of the most important global health problems of our time, and strongly overlap in sub-Saharan Africa [1]. The detrimental effects of this interaction may be especially relevant during pregnancy, with adverse outcomes for both the mother and the infant [2,3].Vertical transmission of HIV occurs at an approximate rate of 25-40% in untreated breast feeding populations [4,5]. Maternal RNA viral load [2,6,7] [6,7,11], it has been suggested that malaria, by increasing the replication of HIV, may increase the risk of MTCT [2,6]. However, studies assessing the impact of placental malaria (PM) on MTCT have produced conflicting results, suggesting either that PM could increase MTCT or that low-density PM parasitaemia could decrease MTCT [6,7,17,18]. Pregnant women are especially susceptible to malaria infection, which is associated with considerable maternal and infant morbidity and mortality. The World Health Organization recommends that pregnant women in stable transmission areas receive intermittent preventive treatment (IPTp) with sulfadoxine-pyrimethamine (SP) and sleep under insecticide-treated nets (ITNs). However, the efficacy of the concomitant use of these two interventions has not been evaluated. IPTp consists of the provision of two doses, at le...

Mother‐to‐Child Transmission of GB Virus C in a Cohort of Women Coinfected with GB Virus C and HIV in Bangkok, Thailand

“…A mechanism for the strong inverse association between infant GBV-C and HIV infection that we observed remains unknown. Because both HIV and GBV-C infection appear to be vertically acquired by infants at approximately the same time [22], it is possible that either virus may inhibit the other or that a third factor (e.g., placental inflammation, which has been associated in some studies with reduced MTCT of HIV [47][48][49]) or the infant's cytokine milieu prevents coinfection with both viruses. However, because GBV-C appears to reduce replication of HIV in vitro, most strongly when the cell is infected with GBV-C first, but also when the cell is infected simultaneously with HIV and GBV-C [17], there is a biologically plausible basis for the reduction of MTCT of HIV through infant GBV-C infection.…”

Placental malaria, maternal HIV infection and infant morbidity

“…11,17,22 Three studies suggested that placental malaria was a risk factor for MTCT, with adjusted risk ratios of 2.89 (1.12-7.52), 22 7.9 (1.3-48.4) 17 and 2.0 (1.1-3.9). 11 In contrast, two studies concluded that malaria had a protective effect [adjusted OR 0.23 (0.06-0.89) 15 and adjusted RR 0.4 (0.2-0.6) 11 ].…”

“…11 In addition, baseline antimalarial immunity (related to gravidity and level of malaria transmission) and severity of HIV infection (in terms of CD4 cells count and HIV viral load) may modulate the degree of interaction. These contrasting effects might also be explained, at least partly, by methodological differences between studies, including variation in the diagnostic tool for placental malaria (thick blood smear vs polymerase chain reaction or biopsy), statistical power (some studies probably being underpowered 15,21 ) and statistical adjustment (particularly of HIV viral load).…”

“…In the late 1990s, two ecological studies found that MTCT was higher when deliveries had occurred during or just after the rainy season, suggesting a potential role of malaria. 18,19 To date, six cohort studies have assessed this issue, with contradictory results ranging from no significant effect 20,21 to a protective 11,15 or, on the contrary, a facilitating effect of malaria on MTCT. 11,17,22 Three studies suggested that placental malaria was a risk factor for MTCT, with adjusted risk ratios of 2.89 (1.12-7.52), 22 7.9 (1.3-48.4) 17 and 2.0 (1.1-3.9).…”

“…15 Women infected by HIV and malaria are at greater risk of developing anaemia, and the association of the two infections seems to have a synergistic effect, particularly on severe anaemia (haemoglobin ,8 g/dL) in multigravidae. 8,16 Birth outcome.…”