Co-Infection with Milder Related Parasite Appears to Partially Protect African Cattle from Deadly Fever Caused by Tick-Borne Theileria parva; Finding May Provide Lesson for Malaria and Other Parasite-Caused Diseases

African cattle infected with a lethal parasite that kills one million cows per year are less likely to die when co-infected with the parasite's milder cousin, according to a new study published online on March 20, 2015 in an open-access article in Science Advances. The findings suggest that "fighting fire with fire" is a strategy that might work against a range of parasitic diseases. The immediate implications are for the battle in Africa against a tick-borne cattle-killing parasite, Theileria parva, which causes a disease called East Coast fever. The disease kills one cow every 30 seconds and claims US $300 million in livestock losses each year, mostly from poor herders who can scarcely afford to lose even a single animal. "Our results suggest seeking a simple vaccine that could protect cows from East Coast fever by inoculating them with a related, but far less harmful, parasite," said lead author Dr. Mark Woolhouse, who is with the University of Edinburgh, in the United Kingdom. "It has been suggested that a similar process might be at work in malaria, where infection with the less harmful Plasmodium vivax parasite may protect people from the Plasmodium falciparum parasite that kills almost 600,000 people each year." The study, titled “Co-Infections Determine Patterns of Mortality in a Population Exposed to Parasite Infections,” was conducted as part of an Infectious Diseases of East African Livestock (IDEAL) project, a multi-partner study that includes the Nairobi-based International Livestock Research Institute (ILRI). The project followed more than 500 indigenous East African shorthorn zebu calves during their first year of life. The calves live in a part of Western Kenya where they are routinely exposed to both the T. parva parasite and its less aggressive relatives. T.
Login Or Register To Read Full Story