[The dilemma of listeriosis control by the public health office].

The frequent occurrence of Listeria monocytogenes both superficially and in certain foods requires measures in accordance with the Federal Laws on Communicable Diseases and Safe Foods to study possible sources of the infectious agent and prevention if positive findings are reported. On the other hand, due to good defence mechanisms, the majority of the population are not at great risk. This excludes, however, immunodeficient patients, aged persons and newborn. The Federal Law on Notifiable Diseases requires only the reporting of meningitis and encephalitis as well as of listeriosis in newborn. Hence, Listeria infections with other syndromes are not registered. The some-times relatively long time of incubation and the lack of knowledge on mild and transient forms of listeriosis render the search for sources of such infections rather difficult. This results in a true dilemma. -Thus, it appears at the present to be more important to encourage strongly the producers of Listeria-endangered food, to eliminate the risk by all possible means. This, however, appears to be applicable only in a few food items. Therefore, the consumer should be more thoroughly informed, so that at least for the 'at risk' part of the population any possible danger may be minimised. Particular attention should be paid to impart good knowledge on the possibilities of preventing listeriosis by appropriately efficient methods of food preparation.