Ovalocytosis disorder found to protect against malaria

A multinational group of researchers has found a strong connection between an inherited red blood cell disorder and protection against Plasmodium vivax malaria.

The research team, led by Ivo Mueller from the Walter & Eliza Hall Institute, genotyped 1,975 children to examine the association between ovalocytosis and P. vivax malaria. Ovalocytosis is an inherited disorder that affects red blood cell shape and can protect against P. vivax malaria. The results of the study suggest that P. vivax malaria may have contributed to genetic adaptations to malaria in Oceanic and Asian populations, Science Daily reports.

"It has long been assumed that Plasmodium falciparum, the species that causes the most severe disease and most deaths from malaria, is the most important driver of this gene selection in humans," Mueller said, according to Science Daily. "Our results suggest that P. vivax malaria, though until recently widely considered to be a 'benign' form of malaria, actually causes severe enough disease to provide evolutionary selection pressures in the Asia-Pacific."

The researchers were interested in finding out if the P. vivax malaria could be the cause of the high rates of ovalocytosis among Southeast Asian populations. SAO occurs in approximately 10 to 15 percent of the population in some areas of the Southwest Pacific. The findings could result in changes for future malaria vaccine development and design, according to Science Daily.

"Studying the mechanisms that cause SAO-positive people to be protected against P. vivax malaria could help us to better understand the mechanics of infection and help us to identify better targets for a malaria vaccine," Mueller said, according to Science Daily.