Staff of ILRI’s Tick Unit dissect ticks to extract the parasite Theileria parva, which causes East Coast fever in cattle (photo credit: Brad Collis).
A vaccine that protects cattle against East Coast fever, a deadly disease in eastern and central Africa, is being developed by scientists in Kenya working for the International Livestock Research Institute (ILRI) jointly with scientists at the Agricultural Research Service (ARS) Animal Disease Research Unit in Pullman, Washington, which is part of the United States Department of Agriculture (USDA). ARS is the USDA’s chief intramural scientific research agency. This research, which looks at combination vaccines for tick-borne diseases, supports USDA’s priority of promoting international food security.
Scientists are focusing on the tick that transmits the parasite responsible for East Coast fever. Because this host tick and its parasite are similar to the tick and parasite that cause babesiosis, commonly called Texas cattle fever, in the United States, developing a vaccine for East Coast fever could lead to a vaccine for Texas cattle fever, which is a serious illness for wild and domesticated animals, especially cattle.
In an initial study, scientists developed a polymerase chain reaction test that detects parasite DNA in ticks. They used tick populations that were produced at ILRI to have different susceptibilities to infection with the parasite. Two different strains of ticks—Muguga and Kiambu—were compared. The Muguga ticks had a low level of parasitic infection, whereas the Kiambu ticks were highly susceptible.
Understanding genetic differences between these two tick populations could lead to the identification of proteins that might be good targets for a vaccine to help control East Coast fever.
This international partnership is part of a global community effort to control diseases that limit food and fiber production. Although East Coast fever isn’t currently a problem in the United States, this collaborative research aids in keeping the US and other countries free of the disease. Results of this collaborative research may be applied to help control similar parasitic diseases.
Findings from this research were published in Gene and in the Journal of Medical Entomology.
Read more at the United States Department of Agriculture Agricultural Research Service: Partnership focuses on developing East Coast fever vaccine, 4 Oct 2011.
Read more about this research in the October 2011 issue of Agricultural Research Magazine.
Read more about this project on ILRI’s website.