Q1.What are the kinds of "intestinal infections" that many Japanese people suffer from? Please inform us about the major intestinal infections.
It is always a problem when living in groups and the norovirus is extremely common. Outbreaks can easily occur and it is especially prominent among intestinal infections.
Every year in Japan, over 14,000 patients are reported, however, the symptoms are not serious and so there are some who do not seek medical treatment. Therefore the actual situation can be thought to be more than 10 times or even 100 times this number. Because there is no immunization, some people are infected multiple times.
The most common cause of infection in Japan is the habit of eating raw oysters. The reason for this being common between November and February is probably because of eating raw oysters during winter.
Academically, the norovirus is not limited to oysters and can be found concentrated in bivalves. Of course, cooking it will render them safe to eat and there are also oysters that can be eaten raw in the summer such as the summer oysters from the Sea of Japan. All causes of infection are not because of oysters.
Becoming infected orally with norovirus will cause severe diarrhea, vomiting and much suffering; however, it will rarely be serious enough to cause death. It is basically similar to influenza and people will recover from it in 3 to 4 days.
However, there have been cases where elderly persons have died after being infected. In most cases, the cause of death is not the infection itself but rather choking on matter from vomiting or from dehydration because of diarrhea.
Additionally, in recent years in Japan, what has increased is intestinal infections caused by Campylobacter. Infection is caused by eating half-cooked chicken, etc. When imported frozen chicken was examined, Campylobacter was detected in almost 70%. Therefore, you should make sure the chicken is appropriately cooked.