Abstract
Studies of El Tor cholera Vibrio have been studied by a great many workers in the past.
Unfortunately, however, the biological study of El Tor cholera Vibrio is still meager. And the growth and survival of El Tor cholera Vibrio in foodstuffs is a important problem of infection. Therefore, several experiments were conducted. The first experiment was made with the object of clarifying the vital time of El Tor cholera Vibrio in cola, alkali ion drink, milk, coffee, peptone solution and soy sauce. The second was made, increase or decrease of the number of El Tor cholera sticking to raw fish and raw meat in settled temperature. The third, whether El Tor cholera Vibrio was accumulated in short-necked clams in artificial sea water which was contamined with El Tor cholera Vibrio.
Factors influencing the survival of El Tor cholera Vibrio were studied. Results obtained were followings.
1) El Tor cholera Vibrio became extinct within 5 min in soy sauce of a high salt concentration and within 15 min in cola and alkali ion drinks of high acidity. But they did not extinct up to 60 min in milk, coffee and peptone solution.
2) El Tor cholera Vibrio sticking to raw fish or raw meat survived longer at 8°C than at 16°C or 24°C. The number of surviving El Tor cholera Vibrio increased temporally but decreased lator. The number of its increase was positively corelated with the degree of environmental temperature.
In addition, when short-necked clams were placed in artificial sea water which had been contaminated with El Tor cholera Vibrio, it was found that organisms were accumulated and survived within short-necked clams.
