prevalence and molecular characteristics of vibrio species in pre ...

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Today export countries must adapt those rules and regulations to maintain
trade opportunities. It appears that many countries, especially the poorest may face a
major problem in meeting food safety standards that are obligatory in a number of
importing countries.
2.7 Vibrio
2.7.1 History and Morphology
The first Vibrio spp. identified was Vibrio cholera, discovered in 1854 by the
Italian physician Filppo Pacini during an outbreak and subsequent investigation in
Florence. Pacini detected V. cholerae in all intestinal mucosal samples of fatal
victims. John Snow (1813-1858) studied the epidemiology of cholera in several cities
of England and found that cholera is spread by the contaminated water and suggested
pure water for drinking (Thompson et al., 2004).
According to the Bergey’s Manual (Holt et al., 1994) this bacteria is in the
family Vibrionaceae and genus Vibrio and has characteristics of straight or curved
rods, (0.5-0.8µm in width and 1.4-2.6 µm in length), motility by one or more polar
flagella, Gram negative, chemoorganotropic, facultative anaerobic, mesophilic,
oxidase positive and sensitive to the vibriostatic agent O/129 (except a few species).
Most species grow well at 37°C. Vibrio is distributed worldwide and is found in sea
water, fresh water, brackish water and associated with aquatic animals, sediments and
feeds (Bhaskar et al., 1998). Large numbers of Vibrio and Photobacterium attach to
the external surface of the zooplankton and make bio films. Because of this close
association with zooplankton, it is assumed that cholera outbreaks are linked to
planktonic blooms and rising sea water temperature due to global warming
(Thompson et al., 2004).