Researchers working as part of an international team have taken the first step in developing a new type of vaccine to protect chickens against coccidiosis, the most important parasite of poultry globally.

A vaccine of this type – based on proteins from the coccidiosis bug rather than being derived from a live parasite – could be produced on a larger scale than is currently possible and could therefore be used to provide much more widespread protection to chicken flocks. A statement from the BBSRC, who part funded the research sad this could provide a key element in ensureing greater food security in the future.

The researchers have produced a much more detailed picture of how coccidiosis attacks chickens, uncovering the protein molecules which are secreted onto the surface of the coccidiosis-causing-parasite, Eimeria, that allow it to attach to and invade cells in a chicken's gut. The scientists also found that when purified and used to inoculate chickens, one of these molecules provided the birds with some protection against coccidiosis and so shows promise as the basis of a new vaccine.

The progress in research was reported in yesterday’s PLoS Pathogens journal; the UK-based research took place at Imperial College London, the Institute for Animal Health, the University of Oxford and the Royal Veterinary College.

Professor Fiona Tomley of the Royal Veterinary College said, "Coccidiosis is the most important parasite of poultry globally. Conservative estimates by the EU put the annual worldwide cost of coccidiosis at over £1 billion so controlling it is very important economically but it is also valuable for improving the health and welfare of chickens."

Currently, coccidiosis is treated with antimicrobial drugs or using a vaccine derived from a live parasite. Both of these methods are problematic as drug resistance is widespread and the vaccine is relatively expensive to produce so cannot be used on a wide, preventative scale. Vaccines for some other diseases are based on single proteins rather than killed versions of the disease-causing bug. These so-called 'recombinant vaccines' offer a number of advantages over killed-disease vaccines as they are safer and can be produced more cheaply and quickly and on an industrial scale.