Eimeria species parasites as novel vaccine delivery vectors: Anti-Campylobacter jejuni protective immunity induced by Eimeria tenella-delivered CjaA

► First Eimeria expression of a gene encoding an anti-bacterial vaccine candidate. ► E. tenella vectored CjaA vaccination reduced chicken Campylobacter jejuni shedding. ► First use of transgenic E. tenella to vaccinate against a non-eimerian pathogen.