Parasite sheds light on sleeping sickness

Fresh insight into the survival strategy of the sleeping sickness parasite could help inform treatments for the disease. University scientists have found that the parasite, which can transform itself into either of two physical forms, has developed a careful balance between these. One of these types ensures infection in the bloodstream of a victim, and the other type is taken up by the tsetse fly and spread to another person or animal. Balanced approach. The parasite maintains a trade-off between maintaining enough parasites to beat off the immune response and cause infection, and ensuring sufficient parasites to enable the spread of the disease. Researchers used a combination of biological and mathematical techniques to show how the parasite balances production of each of the forms. Their results enable fresh understanding of how the parasite reacts to its surroundings to ensure its survival in the short term as well as the long-term spread of the disease.