Outbreaks of disease are usually associated with a change in environmental conditions. Stressors, including overcrowding, high temperature, a sudden change of temperature, rough handling, transfer of fish, low dissolved oxygen, poor nutritional status, and fungul or parasitic infection, contribute to physiological changes and heighten susceptibility to infection. Avoid hatchery to hatchery transfers of fish. Fish gradually develop resistance to local strains of bacteria but may carry virulent organisms to another hatchery when transferred. Provide optimal environmental conditions for the species being reared, paying special attention to the maintenance of oxygen levels and the gentle handling of fish.
Prophylactic treatments are helpful when sorting, handling, or moving broodstock.
Antibiotics or disinfectants should be added to the water as a prophylactic measure when fish are transported in tank trucks or plastic bags. Therapy Chemotherapeutic agents are used for the treatment of A. hydrophila in fish farms. Reports of Aeromonas wound infections have appeared increasingly in the literature. Unlike gastroenteritis, these infections can have fatal or serious debilitating outcomes, such as amputations. Myonecrosis and ecthyma, the two less commonly seen types of Aeromonas infections, are typically found in patients that are immunocompromised.