Mosquito-Transferred Malaria Lowers Severity of the Symptoms
Malaria, a disease caused by parasites transferred via mosquitos, can result in deadly repercussions when left untreated. Malaria continues to afflict and kill people globally each year, with the most concentrated number of cases in Africa. The U.S. Centers of Disease Control and Prevention (CDC) reported that 91 percent of malaria-related deaths happened in the African region back in 2010. The fight against malaria continues as more research is being done to find new treatments and preventative measures. In a new study headed by Dr. Jean Langhorne from the Medical Research Council National Institute for Medical Research and colleagues, they reported that the severity of malaria symptoms appear to 'reset' when mosquitoes pick up the parasite and transfer it.
"Understanding how malaria becomes more or less virulent is central to understanding how to manage and treat the disease," says senior author of the study, Dr Matt Berriman, who is from the Wellcome Trust Sanger Institute, according to Medical Xpress. "We studied a rodent malaria species, that exhibits many of the same responses as seen in a human malaria infection. Our understanding of how the parasite interacts with the immune system is fundamentally changed by this study."
The research team compared the two different routes of transmission for malaria. The first route, which is also the most common one, occurs when a mosquito transfers the parasite. The second route occurs in the lab where the experimenters repeatedly exposed mouse models to the malaria parasite via blood samples. The researchers knew that the second route results in a more severe set of symptoms from the infection. However, the researchers did not know why this occurs. After studying the gene activity of the parasite, the researchers discovered a specific gene family known as the Cir genes. These genes contributed to how a body's immune system fought off the infection and how severe the symptoms of the infection would be.
The researchers also looked into the gene activity of the parasite as it goes through its life cycle in the host's body. They found that P.c.chabaudi seems to reset the genetic activity of the parasite when it gets transferred by mosquitoes, which resulted in a less severe case of malaria. The researchers hope that these findings could provide a better understanding of how the body fights off malaria, which would then help with creating an effective vaccine against the infection.
"Our research is helping to better understand vaccine targets," said Dr Adam Reid, of the Wellcome Trust Sanger Institute and another author of the study. "RNA sequencing allowed us to identify a set of Plasmodium genes that control the immune response and the degree of severity of the disease in mice. We anticipate that we will be able to transfer the findings from our study in mice to human malaria studies, the next phase of our research."
The findings were published in Nature.