Immigration of Ethiopians with typhoid fever to Israel: apparent lack of influence on the local population.

The epidemiology of typhoid fever in Western countries may be affected by immigration from developing countries. We studied the immigration of Ethiopian Jews to Israel to find the effects of an influx of many individuals infected with typhoid into an area with a low incidence of the disease. Typhoid fever affected 204 Israelis and 121 (1.1%) of 10,654 Ethiopian immigrants during the period of 1984-1985. Of those Ethiopian cases, 107 occurred during a 3-month period. During the 5 months following that 3-month period, there was no increase in the number of cases of typhoid among Israelis. Although after that time there was a local waterborne outbreak of typhoid that affected 83 Israelis, no Ethiopians resided in the area where the outbreak occurred; therefore, we concluded that these 83 cases of typhoid fever were not related to the immigration of Ethiopians into Israel. In fact, if those 83 cases were excluded from the statistical analysis, there was no increase in the occurrence of typhoid during the 2-year period studied. Therefore, the immigration of many people with typhoid into an area of low incidence does not necessarily confer a risk of infection to the local population.