Vibriosis and Luminal Bacterial Disease in Shrimp

SYNONYMS
Luminescent shrimp disease, Fire-fly disease

INTRODUCTION
Commercial shrimp culture in Asia and Latin America has suffered huge mortalities due to bacterial pathogens belonging to the genus Vibrio. 

Vibriosis affects all stages of shrimp development but juveniles during the first 30 to 80 days after transfer to the grow-out ponds are especially susceptible.  

Some Vibrio strains are luminescent and infected shrimp often appear luminescent at night, hence the name luminescent shrimp disease or fire-fly disease. Infections of the exoskeleton often develop into a digestive tract infection, including the hepatopancreas, and eventually systemic septicaemia occurs. 

ETIOLOGY
The most frequently encountered Vibrio  spp. in hatchery and grow-out facilities are V. harveyi, V. parahaemolyticus, V. vulnificus and V. alginolyticus. 

These are Gram-negative, motile, rod-shaped bacteria that require NaCl for growth