Evidence that water transmits the disease caused by the fish pathogen Photobacterium damselae subsp damselae

The transmission through water of the disease caused by the fish pathogen, Photobacterium damselae subsp. damselae, as well as the role of the skin mu cus in the initial steps of the infection, have been studied. All tested st rains resisted the bactericidal activity of the mucus and showed an ability to adhere to it, but only those virulent by the intraperitoneal route were infective through water. Moribund fishes showed the typical signs of the d isease: haemorrhaged areas on the body surface and ulcerative lesions with mucus degradation. These results suggest that the pathogen can be transmitt ed to fish through water and use the skin as a portal of entry.