No vaccine is capable of conferring general protection against diarrhoea, which has many different causes. However, the new injectable Vi polysaccharide vaccine, given in one injection, is well tolerated and provides good protection. A booster dose is recommended every three years, and possibly more often for travellers to places where conditions of hygiene are poor. Another alternative is to use the oral live typhoid vaccine which is effective when given in three oral doses two days apart. To reduce the risk of infection, travellers must take great care about what they eat and drink.
Dehydration can be dangerous at any age but is particularly so in small children.
Cholera can cause extremely rapid and large losses of water and salts through profuse vomiting and diarrhoea, even in adults. They should never be used by children. Bacterial dysentery, protozoal infections and intestinal helminthic infections require specific treatment.