ARS | Publication request: Live Attenuated Bacterial Vaccines in Aquaculture

Submitted to: International Symposium on Talipia in Aquaculture
Publication Type: Proceedings
Publication Acceptance Date: April 1, 2011
Publication Date: April 18, 2011
Citation: Klesius, P.H., Wei Pridgeon, Y. 2011. Live attenuated bacterial vaccines. In: L. Liping and K. Fitzsimmons (Eds). Proceedings of the Ninth International Symposium on Tilapia in Aquaculture. p.18-26.

Interpretive Summary: Aquaculture is emerging as an important economical agribusiness, worldwide. Disease outbreaks cause severe economic losses in aquaculture production and trade. In addition to mortality and morbidity, disease causes reduced slaughter value, growth performance and feed conversion in fish. Other costs associated with disease are money spent to purchase chemicals and drugs to combat diseases. The best disease prevention method is vaccination. Vaccines are an integral tool in any health management strategy. Researchers at the USDA, ARS Aquatic Animal Health Research Unit in Auburn, Alabama have developed effective vaccines against highly pathogenic bacteria species. The vaccine technology involves preventing infection by the initiation of acquired immunity in the immunized fish. Bacterial species of more than 20 genera have been reported as causes of diseases. Bacteria cause disease in more than 20 species of fresh and marine water food fish. The economic loss due to these pathogens is estimated in hundreds of million dollars, annually. Fish infected with these pathogens suffer high mortality and greatly reduced growth rates. Killed vaccines are most effective when delivery by injection with delivery by injection which is not a cost-effective method of fish immunization. Attenuated vaccines offer a better alternative to killed vaccines.

Technical Abstract: Aquaculture has emerged as an important economical agribusiness, worldwide. Among the top barrier to growth of aquaculture is infectious disease that is causing severe economic losses. Bacterial species of more than 20 genera have been reported as causes of diseases. The risk of disease is often very high, especially in intensive and recirculation culture systems. The best prevention of disease is vaccination. Vaccines are an integral tool in any health management strategy to economically rearing food fish. Live attenuated vaccines have been extensively and very successfully used against a number of animal and human diseases. Live attenuated vaccines naturally mimic the interactions between the host and the pathogen which best led to the optimal protective immune responses. Thus, the most valid preventative strategy in the fight against infectious disease of fish is live attenuated vaccines. In addition, the advantages of such vaccines include relatively low production cost, easy delivery method and the long duration of protection. Aspects of biosafety, efficacy, economic benefits, methods of production and delivery, some of the available and promising live attenuated bacterial vaccines will be discussed.