[Hodgkin's disease: an epidemiological study on 140 children--urban/rural relation, profession of parents, domestic animal contact].

In Northern Germany (Schleswig-Holstein, Niedersachsen, Hamburg and Bremen) 140 children aged 2-14 years who had developed Hodgkin's disease after World War II were identified with the help of all 54 children's hospitals, the 101 local public health offices, and the Hamburg Cancer registry etc. Only histologically confirmed cases were included. For boys, comparison by urban and rural residence showed a preponderance of cases in rural areas (places with less than 2000 inhabitants). This urban-rural difference became statistically significant (P less than 0.05) when the cases reported from Hamburg (with its greater registration intensity) were excluded. For girls, there was no difference in the urban/rural distribution. Personal interviews were conducted with 133 case families. One third of the parents had been engaged in agricultural occupations. In the retrospective studies contacts with domestic animals was most impressive, especially those with rabbits (84.2%). But there was also contact with large animals, most frequently with pigs (45.9%). The difficulties of getting suitable controls--because of the widespread and changing keeping of animals--are discussed. A matched pair analysis of the 21 children from Hamburg confirmed significance (P less than 0.05) for contact with domestic rabbits.-- Furthermore, multiple cases (in family or in neighbourhood, "cluster") could mostly be linked together by contacts with the same herd. The epidemiological results from the basis of a hypothesis that Hodgkin's disease is a zoonosis. The possibility of a synergistic action of two factors--transmitted by two different species--is discussed.