Geographical Range And Preferred Environmental Conditions For Vibrio Vulnificus

Vibrio Vulnificus (Vv) occurs naturally and found in Free State in maritime and estuarine environment all over the world. This bacterium prefers to grow in tropical and subtropical climate and favorable temperatures are 9 to 31°C which shows that it is found in warmer marine water. It generally increases its number where temperature is more than 18 °C.

Taking the US into consideration, it majorly present in the area of states which shares border with Gulf of Mexico and also been found in regions like New England and the northern Pacific Coast (Reference). It has also been observed that temperature less than 10 °C the quantity of Vv lost the detection ability and also Vv go into viable but non cultural phase under 10 °C. A complete count of viable Vv found in any region goes up and down depends on the temperature of water. As said earlier that Vv go into viable but non cultural phase below 10 °C irrespective of the presence or absence of nutrients in the culture. The overall change in the structure and shape from rod to cocci occurs in Vv and cocci become small with variation in lipid profile, expanded mechanical resistance in cell wall and decreased transport of amino acids. Recovery of the Vv bacteria from viable but non cultural phase can be done by increasing temperature slowly and slowly in medium that have no nutrients, which might be closely resembling the steady warming of seaside waters in the spring. V. vulnificus can be discovered free-living, and may connect with zooplankton.

Apart from warmer temperature, amount of salt present in seawater also affects the growth and number of Vv as it is generally found in small to adequate content of salt mainly in the range between 15-22 ppt. Salinity more than this causes negative effect on Vv. This means that temperature is directly proportional to growth of Vv but salinity is inversely proportional to number of Vv. It had also been observed that high number of Vibrio Vulnificus are found in the area which has salinity from 5 to 10 ppt regardless of the temperature of the water, which shows ideal saltiness for their growth.

So it can be said that Vv can be found in warmer water bodies with low amount of salinity. Particularly the countries suffering from this are the USA, Gulf of Mexico, Brazil, Denmark, Turkey, Korea, Japan India etc.