Silent Malaria Infections Not Harmless: Study

An Australia-led study has found that "silent" malaria can disrupt immune function, challenging long-standing beliefs about asymptomatic malaria infections.    

The study focused on Plasmodium vivax, the most widespread malaria parasite and a major obstacle to global elimination efforts, according to a statement released Monday by Australia's Monash University.    

While people in malaria-endemic regions often carry the parasite without showing symptoms, these "silent" infections were traditionally seen as beneficial, thought to help maintain immunity and prevent future illness, the statement said.    

However, the new findings, detailed in the journal Molecular Systems Biology published by the European Molecular Biology Organization, suggest that these sub-clinical infections may actually impair the immune system.    

Researchers used a systems immunology approach to examine blood samples from individuals with both symptomatic and asymptomatic P. vivax infections, and found that both groups showed signs of immune dysfunction, particularly in monocytes, cells that play a key role in fighting infections.    

In symptomatic cases, monocyte-related genes were strongly suppressed, and critical immune cells were depleted. Even in asymptomatic individuals, gene activity linked to monocyte function and inflammation was disrupted, the study showed.    

The study found increased activity in anti-inflammatory pathways and immune checkpoint receptors, indicating that the immune system is actively suppressed during P. vivax infection.    

"Asymptomatic malaria is not as harmless as previously believed," as it can suppress key immune functions, potentially reducing the body's ability to eliminate the parasite, fight off other diseases, or respond effectively to vaccines, said Diana Hansen, co-head of Monash University's Infection Discovery Program.    

The research advances understanding of malaria's impact on the immune system and highlights the need to reconsider public health strategies in endemic regions, advocating for screening and treatment to curb transmission. – Xinhua/RSS