Farmed Salmon Disease Prevention: Vaccination and Its Welfare Benefits

Vaccination has transformed salmon aquaculture welfare in Norway and Scotland by dramatically reducing antibiotic use and the disease burden driving it.

Key Facts

Norway reduced veterinary antibiotic use in salmon farming by over 99% between 1987 and 2012 primarily through vaccination
Multi-component oil adjuvant vaccines protect against bacterial diseases including furunculosis, vibriosis, and cold water vibriosis
Oil adjuvant vaccines cause injection site reactions that can cause welfare concerns if not carefully managed
Vaccine development for viral diseases including ISA and SAV is advancing but remains less complete than bacterial disease vaccines
Vaccination programs require careful timing, appropriate storage, and trained staff for maximum welfare and efficacy benefit

Welfare Considerations

Salmon vaccination welfare is overwhelmingly positive — the diseases prevented cause far greater suffering than the vaccination procedure itself. Norwegian salmon aquaculture demonstrates what is possible when vaccination programs mature: near-elimination of antibiotic use and the disease-driven mass mortality events that cause widespread fish suffering. The residual welfare concern is injection site granuloma formation with some oil adjuvant vaccines, which causes localized inflammation and potential internal scarring. Vaccine formulation research aimed at reducing adjuvant-related pathology while maintaining efficacy addresses this remaining welfare concern.

What You Can Do

Choose farmed Norwegian or Scottish salmon with documented vaccination programs and low antibiotic use
Support research into vaccine formulation improvements that reduce injection site reaction welfare concerns
Advocate for mandatory vaccination program reporting as a component of salmon welfare transparency
Engage certification bodies about including vaccination coverage rates as a welfare certification criterion
Support development of disease vaccines for viral salmon pathogens that would further reduce disease welfare burden