Scientists discover malaria parasites communicate with each other

Melbourne scientists reported on Tuesday that malaria parasites "talk" to each other to increase their survival and transmission rate, which may change the way malaria vaccines are developed.

Professor Alan Cowman and Dr. Neta Regev-Rudzki from the Walter and Eliza Hall Institute's Infection and Immunity division led the study, along with colleagues from the University of Melbourne's Bio21 Institute and Department of Biochemistry and Molecular Biology. The study was published in the journal Cell on Tuesday.

The findings of the study proved malaria parasites communicate with one another within the human body to optimize their life spans and probability for transmission to other humans. Cowman said the parasites work together in unison to enhance "activation" into sexually mature forms so they can be detected by mosquitoes and carried to another human.

"When Neta showed me the data, I was absolutely amazed, I couldn't believe it," Cowman said. "We repeated the experiments many times in many different ways before I really started to believe that these parasites were signaling to each other and communicating. But we came to appreciate why the malaria parasite really needs this mechanism -- it needs to know how many other parasites are in the human to sense when is the right time to activate into sexual forms that give it the best chance of being transmitted back to the mosquito."

Regev-Rudzki said the parasites communicate with one another inside red blood cells by sending packages of DNA from one parasite to another. It is a social behavior, Regev-Rudzki said, that allows the parasite to infect humans, then change its make-up to best survive in the body of a mosquito before it reaches another human.

"This discovery has fundamentally changed our view of the malaria parasite and is a big step in understanding how the malaria parasite survives and is transmitted," Cowman said. "The next step is to identify the molecules involved in this signaling process, and ways that we could block these communication networks to block the transmission of malaria from the human to the mosquito. That would be the ultimate goal."