The Libyan Creutzfeldt-Jakob disease focus in Israel: an epidemiologic evaluation.

In a country-wide study of Creutzfeldt-Jakob disease (CJD) in Israel, we diagnosed 114 cases, among them 49 Libyan-born, with onset of their disease during the years 1963-1987. After age adjustment, the mean annual incidence rate per million population was 43 among Libyan-born and 0.9 in the rest of the population. Among Jews born in Egypt and Tunisia, neighboring countries of Libya, the adjusted rates were higher than in the other Israelis (3.5 and 2.3 per million, respectively). Among Libyan Jews, there was no association between incidence rate of CJD and age at immigration, ie, duration of exposure to hypothetical infectious factor in Libya. The percent of familial cases among Libyan Jews (41 to 47%) is one of the highest ever published. Genetic factors seem to be important for the high incidence of CJD among Libyan Jews.