DNA Vaccines for Fish

Abstract

Aquaculture has been playing an important role in global food security for the last three decades. To meet the increasing consumer demands, fish farming has shifted from extensive to intensive industrial-scale production. However, this intensification has led to frequent occurrences of infectious diseases, hampering the development and profitability of fish farms. To control the persistent and emerging diseases and sustain the intensive fish production, aquaculture industry requires a wide number of effective vaccines. Although there have been significant progress in the field of fish vaccinology, only few traditional inactivated vaccines, mostly against pathogenic bacteria, got licenses till date. Thus, there is urgent need for effective prophylaxis against other serious fish pathogens, viz., viruses, parasites, and intracellular bacteria. In this regard, DNA vaccination has come as a promising alternative strategy in fish vaccinology. It involves delivery of plasmid DNA, encoding a vaccine antigen to the host, which in turn expresses the antigenic protein and induces strong and long-lasting immune responses inside the host. In this chapter, the key aspects relating to DNA vaccination in aquaculture, viz., action mechanisms, current status, underlying challenges, existing opportunities, and future directions regarding the use of DNA vaccines in commercial fish farming are reviewed and discussed.