Infectious Hematopoietic necrosis was observed for the first time in France in April 1987 in a freshwater rainbow trout farm in the northern area. The International Office of Epizootics was immediately notified. The disease appeared in a second salmonid farm, not farm from the first, perhaps after exchange of materials.
In the two cases, fry and fingerlings were diseased (about 50% mortality), but not adults or commercial sized fish which did not carry the virus. The French Veterinary Services intervened for control measures: commercial fish can only be used for human consumption.
The present investigations and laboratory examinations have not detected IHNV in other farms.