[Typhus abdominalis in travelers. Headaches originating in the abdomen].

The incidence of typhoid fever in emerging countries remains high, being estimated to be 500 per 100,000 head of population. Tourists from the industrialized countries can contract the infection in particular when travelling under conditions of poor hygiene in endemic regions. The risk of contracting typhoid appears to be highest on lengthy travels on the Indian subcontinent, while short visits to Latin America or Africa appreciably less often result in an infection. Currently, two vaccines are approved for use in Germany: a live oral vaccine containing the defective S. typhi mutant Ty 21a, and a parenteral inactivated vaccine prepared from the Vi capsid antigen of S. typhi. Both vaccines are well tolerated and provide similar levels of protection. The reported protection rate for the live vaccine varies in various studies between 33 and 67%; that of the inactivated vaccine between 55 and 75%. Medical advice prior to travel should weigh up such risk factors as age, duration of the journey, destination and the nature of the journey. While vaccination is particularly recommended for travelers with one or more risk factors, it should always be pointed out that an infection is nevertheless possible. In view of the fact that immunization against hepatitis A and typhoid fever are often indicated simultaneously, the development of a combination vaccine would be desirable.