Coccidiosis: Recent progress in host immunity and alternatives to antibiotic strategies

Authors: LEE, YOUNGSUB - US Department Of Agriculture (USDA); LU, MINGMIN - US Department Of Agriculture (USDA); Lillehoj, Hyun

Submitted to: Vaccine
Publication Type: Review Article
Publication Acceptance Date: 1/27/2022
Publication Date: 1/29/2022
Citation: Lee, Y., Lu, M., Lillehoj, H.S. 2022. Coccidiosis: Recent progress in host immunity and alternatives to antibiotic strategies. Vaccine. 10:215. https://doi.org/10.3390/vaccines10020215.
DOI: https://doi.org/10.3390/vaccines10020215

Interpretive Summary: Eimeria parasites cause coccidiosis in poultry with significant economic losses which is estimated to be over $13 billion globally. In this review, ARS scientists summarize the latest information on host immunity, vaccine development and alternative strategies to control coccidiosis. Comprehensive understanding of host, parasite and environmental factors that affect avian coccidiosis will facilitate the development economically feasible strategies to prevent and control avian coccidiosis. This review will be a valuable resource for field veterinarians, managers of poultry farms and researchers in coccidiosis and animal diseases.

Technical Abstract: Coccidiosis is an avian intestinal disease caused by several distinct species of Eimeria parasites that damage the host intestinal system, resulting in poor nutrition absorption, reduced growth, and often death. Increasing evidence from recent studies indicates that immune-based strategies such as the use of recombinant vaccines and various dietary immunomodulating feed additives can improve host defense against intracellular parasitism and reduce intestinal damage due to inflammatory responses induced by parasites. Therefore, a comprehensive understanding of the complex interactions between the host immune system, gut microbiota, enteroendocrine system, and parasites that contribute to the outcome of coccidiosis is necessary to develop logical strategies to control coccidiosis in the post-antibiotic era. Most important for vaccine development is to understand the protective role of the local intestinal immune response and the identification of various effector molecules which can mediate anti-coccidia activity against intracellular parasites. This review summarizes the current understanding of the host immune response to coccidiosis in poultry and discusses various non-antibiotic strategies which are being developed for coccidiosis control. Better understanding of the basic immunobiology of pertinent host–parasite interaction in avian coccidiosis will facilitate the development of effective anti-Eimeria strategies to mitigate the negative effects of coccidiosis.