Malaria parasites 'thrive by talking' Malaria parasites "talk" to each other Melbourne scientists have made the surprise discovery that malaria parasites can "talk" to each other- a social behaviour to ensure the parasite's survival and improve its chances of being transmitted to other humans. Scientists have been surprised to learn that malaria parasites "talk" to each other. And the chatter is crucial to the parasite's survival and spread in humans. The breakthrough by researchers from the Walter and Eliza Hall Institute and the Bio21 Institute fundamentally changes scientists' understanding of the parasite, opening up new paths for the development of antimalarial drugs. Head of Walter and Eliza Hall's infection and immunity division Alan Cowman admitted the discovery came as a shock. A breakthrough by Neta Regev-Rudzki and Alan Cowman could help develop new antimalarials. A malaria parasite lives inside a red blood cell, meaning any communication needs to be able to pass through eight membranes and travel the distance between the parasites. "I really didn't think it was possible," Professor Cowman said. I was absolutely amazed when (colleague Neta Regev-Rudzki) showed me the results. But after much re-testing, results confirmed the parasite, which according to the World Health Organisation killed 106,820 people in 2011, does indeed need to communicate to survive and spread. Being able to talk lets each parasite know when the time is right to switch to a sexualised form best able to be transmitted into a mosquito. Malaria is spread by mosquito bites, so returning to the mosquito gives the parasite the best chance to reinfect. "The parasite wants to survive in the host without killing it, so it needs to know how many [parasites] there are and when the best time is to leave the host," he said. The two-year study, published in the journal Cell on Thursday, also established that communication between the malaria parasites increased with stress brought on by changes to its environment. Professor Cowman said this indicated how crucial communication was to the parasite's survival. The messages are sent in "packages" of DNA from parasites living within red blood cells. The challenge for the researchers, including Dr Regev-Rudzki and Dr Danny Wilson, is to shutdown the parasite's communication networks which would stop it being passed on to a new host. One mosquito can carry up to 30,000 malaria parasites in its saliva glands. The parasite is transmitted via the saliva when an infected insect bites. Malaria is among the top three diseases that kill humans. The WHO estimates about 3.3 billion people - half the world's population - are at risk of malaria. In 2011, there were 106,820 reported deaths from the disease in 99 countries.