Post 5: Vibriosis-An Examination of one of the most Recurring Bacterial Diseases in the Marine Environment

In 1997, Japanese researchers captured both juvenile and adult individuals of Estuary Cod, Mangrove Grouper and Napoleon Fish and transported these individuals back to Gondol Research station. In less than a week after transportation, all captured fish had died (Zafran et al 1998).
The cause of which came to be regarded as the most common bacterial disease in marine fishes; Vibriosis-from the genus Vibrio (Zafran et al 1998).

Bacteria in the Vibrio genus have evolved to become highly versatile, as strains of the disease have been documented to infect fish in marine, brackish and freshwater environments (Bullock 1977).
A study on Vibrio cholerea even found significant genotypical and phenotypical trait variations within the individual bacterial species (Cho et al 2010).

Signs of Vibriosis in juvenile fish simply appear simply as having a darker body coloration and a loss of appetite (Munn 2008), with older fish displaying haemorrhaging from hemorrhagic septicaemia and/or ulcerative lesions occurring on the fishes skin. Fish that are infected in the eyes also exhibit eye bulging (Zafran et al 1998).

A control of Vibriosis in an aquaculture or aquarium setting involve maintaining high water quality and a low density of fish within the tank in order to avoid any further stress on the fishes immune system. Administration of antibiotics is also a valid treatment to stop the spread of the disease, usually the use of the broad-spectrum antibiotic; OxyTetra Cycline over an 8-10 day period (Zafran et al 1998).

A snapper with the whole Vibrosis package; darker skin, lesions and haemorrhaging.

Stay tuned for more exciting pathogens and parasites.

References:

Bullock, G 1977, 'Vibriosis in Fish', 'U.S. Fish and Wildlife Service'.

Cho, Y. Yi, H. Lee, J. Kim, D. Chun, J 2010, 'Genomic Evolution of Vibrio cholerae', 'Current Opinion in Microbiology', vol. 13, pp. 646-651

Munn, C 2008, 'Vibriosis in Fish and its Control', 'Aquaculture Research', vol. 8, pp. 11-15

Zafran, A. Rosa, D. Koesharyuni, I. Johnny, F. Yuasa, K 1998, 'Manual for Fish Diseases Diagnosis', 'Japan International Cooperation Agency'.