Streptococcal disease is the most significant infectious disease of farmed tilapia globally, causing significant mortality and welfare suffering. Prevention through vaccination and management is becoming more effective.
Streptococcal disease causes significant suffering through septicaemia, neurological signs, and eye disease before death. Mass mortality events represent welfare catastrophes affecting thousands of individual fish. Vaccination programmes that reduce disease incidence simultaneously improve individual welfare and farm economics. Improving vaccine efficacy and delivery methods is a critical welfare research priority for tilapia.