FRIDAY, SEPTEMBER 30, 2016

Recurrent malaria may lead to chronic inflammation and death

Recurrent infections with malaria can lead to chronic inflammation in blood vessels which may predispose individuals to future infections and increase vulnerability to cardiovascular disease, according to a study published on Wednesday.

The findings of the study, which was conducted by the Wellcome Trust in Malawi, could explain the indirect burden of malaria on childhood deaths in areas where the disease is prevalent and children encounter multiple clinical episodes of malaria per year. The researchers found that blood vessel inflammation from an infection of malaria can remain present in an individual up to one month later.

"These findings suggest that children who live in areas of high malaria transmission have persistently inflamed blood vessels, and that could have significant effects on their long-term health," Chris Moxon, the first author of the study, said. "It could leave them more susceptible to repeated and more severe infections with malaria, but also with other bacteria and viruses, and chronic changes to the blood vessels like these could be an important contributing factor to cardiovascular disease later in life."

Deadly malaria-causing Plasmodium falciparum parasites cause inflammation in blood vessel walls. This makes infected red blood cells more able to cling to the sides and hide away from the immune system. The researchers found that inflammation levels were as much as 22 times higher in patients with a severe form of malaria known as cerebral malaria than in healthy controls one month after the initial infections.

"If follow-up studies in other populations confirm these findings, we should consider whether existing anti-inflammatory drugs such as statins may be able to limit these effects," Rob Heyderman, the lead author of the study, said. "Short courses of statins could be targeted to children with severe and recurrent disease to try and limit the severity of future infections, but this would need to be evaluated in well-conducted clinical trials."

The study was published in the Journal of Infectious Diseases.

Malaria caused by infection with P. falciparum results in approximately 300 million clinical episodes annually. Children living in areas where the parasite is prevalent could receive more than one infective bite of malaria per day leading to multiple clinical episodes in a single year.

Past studies showed that reducing malaria transmission in a population like this can decrease the number of childhood deaths from any cause by up to 70 percent.