Improvement of Theileria parva sporozoite vaccine against East Coast fever
In East and Central Africa, the most important tick-borne disease of livestock is East Coast fever, caused by the intracellular parasite Theileria parva. More than one million cattle die of East Coast fever annually, resulting in approximately CA$361 million in losses. Mortality rates approach 90% in susceptible cattle, and animals that recover are long-term Theileria parva carriers that act as sources of further infection for susceptible cattle.
The main methods of disease prevention rely on restricting cattle movements, tick control, or immunization. The first two methods are difficult to enforce. The immunization method involves inoculation of cattle with a live vaccine and concurrent long-acting oxytetracycline treatment to minimize clinical signs. Although the vaccine is efficacious, its production is cumbersome and expensive. Additional technical challenges include dose standardization, the requirement for a large number of cattle to determine the dose, and tick protein contamination. The requirement for concurrent treatment using long-acting oxytetracycline makes the method even more expensive, consequently reducing adoption.
By end of the 30 months, this project should deliver a streamlined and standardized Theileria parva sporozoite vaccine production process that involves less animal use and validation of a vaccine that needs no concurrent oxytetracycline use. The improved production process will be transferred to both Veterinary Medical Research and Development, Inc., a US-based company, and the Edinburgh, Scotland-based Global Alliance for Livestock Veterinary Medicines (GALVmed) for technology distribution to endemic regions.
This project is funded through the Livestock Vaccine Innovation Fund, a partnership of the Bill and Melinda Gates Foundation, Global Affairs Canada, and IDRC. It represents a joint investment of CA$57 million over five years to support the development, production, and commercialization of innovative vaccines against priority livestock diseases in sub-Saharan Africa, South Asia, and Southeast Asia.