Understanding the Interplay Between Malaria and HIV

Malaria and HIV infection pose significant challenges to global health, particularly in sub-Saharan Africa, where their geographical distributions overlap. In a review published today in The Lancet HIV, researchers from the Barcelona Institute for Global Health (ISGlobal), an institution supported by the “la Caixa” Foundation, examine how both infections interact at the epidemiological, clinical, immunological and therapeutic level. They identify knowledge gaps that should be addressed to guide policy makers in providing optimal prevention, care and treatment for HIV and malaria prevention, particularly among vulnerable populations.

Co-infection and transmission of malaria and HIV

Sub-Saharan Africa accounts for more than 90% of all malaria cases and 67% of people living with HIV worldwide. The overall prevalence of people co-infected with both malaria and HIV is estimated to be 19%.

Available evidence suggests that malaria and HIV have a synergistic effect, with one infection exponentially increasing the adverse effects of the other. This has serious implications for disease management and control efforts: people with both malaria and HIV tend to have worse clinical outcomes, including a higher risk of severe malaria and mortality.

While recent studies suggest that malaria is a risk factor for HIV acquisition, there are discrepancies in how malaria affects HIV transmission across sub-Saharan Africa.

“Although there has been significant progress in understanding the dynamics of malaria and HIV co-infection, there are still critical knowledge gaps that need to be addressed,” says Antía Figueroa-Romero, ISGlobal researcher and first author. “Most studies on HIV and malaria co-infection were conducted before the test-and-treat policy was introduced in 2016, according to which every person diagnosed with HIV should start antiretroviral treatment (ART) regardless of their CD4 cell count, so there is a lack of information in this context.”

Antiretroviral and antimalarial drugs

There is also evidence of antiretroviral and antimalarial drug interactions which may reduce the efficacy of these drugs, both for treatment and prevention. In addition, drugs for preventing malaria in people living with HIV are being evaluated, but to date no specific malaria control strategies have been recommended for these populations, who are at increased risk of contracting malaria.

“There is an urgent need for tailored interventions to address the challenges of malaria and HIV co-infection, especially in vulnerable populations such as pregnant women and children,” says Raquel González, ISGlobal researcher. “In addition, it’s essential that policymakers and healthcare providers consider the interactions between HIV and malaria when developing control guidelines and disease elimination plans.”

Reference: Figueroa-Romero A, Saura-Lázaro A, Fernández-Luis S, González R. Uncovering HIV and malaria interactions: the latest evidence and knowledge gaps. Lancet HIV 2024

Image: Aleix Cabrera/ISGlobal