Pregnant women living with HIV showed a threefold increase in the risk for placental malaria in the context of a high viral load, based on data from more than 600 individuals.
In the absence of intervention, the mother-to-child transmission of HIV ranges from 15% to 45%, said Anete Mendes Muxlhanga, MD, of the Manhica Health Research Center, Manhica, Mozambique, and colleagues in a study presented at the International AIDS Society Conference on HIV Science.
However, data on the factors determining increased antiviral load in this population are limited, the researchers noted.
The researchers reviewed data from 666 pregnant women living with HIV in Africa. The participants were part of a randomized trial conducted in Gabon and Mozambique from 2019 to 2023 that evaluated dihydroartemisinin-piperaquine for malaria prevention in pregnant women who were HIV-positive. Approximately one third of the participants (35%) presented with a high viral load, defined as more than 150 copies/ml.
In a multivariate analysis, both baseline anemia and delayed initiation of antiretroviral therapy (ART) in the antenatal period were significantly associated with high viral load (odds ratios [ORs] 1.75 and 7.71, respectively). In terms of pregnancy outcomes, women with a high viral load were more than three times as likely to contract malaria (OR, 3.28; P = .002), the researchers wrote in their abstract.
The associations of both anemia and delayed ART with increased viral load highlight the need for comprehensive antenatal care, including early ART access, to improve pregnancy outcomes and reduce vertical transmission risk, the researchers wrote in their abstract. “Further research should explore the interplay between viral load and placental malaria,” they added.
Learning More About Viral Load
“Despite widespread availability of ART, elevated antenatal viral load remains a key driver of mother-to-child HIV transmission, particularly in sub-Saharan Africa,” said Jason E. Zucker, MD, an assistant professor of medicine and infectious diseases specialist at Columbia University Irving Medical Center, New York City, in an interview.
“Understanding the current determinants of elevated viral load and its relationship with adverse outcomes like placental malaria is essential for optimizing maternal and infant health,” said Zucker, who was not involved in the study.
“While the association between delayed ART and high viral load was expected, the strong link between elevated viral load and placental malaria was interesting,” Zucker said. “This reinforces emerging evidence of complex immunological interactions between HIV and malaria in pregnancy, which may not have been fully appreciated in previous maternal health frameworks,” he noted. “The magnitude of increased risk (OR, 3.28) was striking and warrants further investigation,” he added.
More Research Needed on Malaria Risk Reduction
The current study findings support the importance of early HIV diagnosis and immediate ART initiation during pregnancy, which clinicians already try to do, Zucker told Medscape Medical News. “Integration of malaria prevention with HIV antenatal care services is also critical, particularly in co-endemic regions, and strengthening these systems could reduce both vertical HIV transmission and malaria-associated complications,” he said.
The current study was limited in part by being a secondary analysis of a randomized controlled trial; therefore, it was not primarily powered to assess determinants of viral load or placental malaria, Zucker noted. “Viral load thresholds and ART regimens may vary regionally, limiting generalizability, and additional prospective studies are needed to confirm causality, explore biological mechanisms linking high viral load with placental malaria, and evaluate whether integrated interventions improve outcomes,” he said.
The researchers had no financial conflicts to disclose.
Zucker had no financial conflicts to disclose.