title: [Epidemiological survey in a natural focus of Rickettsia transmitted by Ixodes ricinus in Switzerland (author's transl)].
abstract: A spotted fever group Rickettsia referred to as "Swiss agent" was detected in 8.5% of Ixodes ricinus collected in a marshy forest of the Swiss plateau. This organism, in its tick vector, was found to be transmitted stadially as well as ovarially; of 433 larval, nymphal or adult ticks from 17 parental tick females, all were infected. A total of 3,612 larval I. ricinus were collected from 168 small mammals including 127 Clethrionomys glareolus, 29 Apodemus sylvaticus and flavicolis, 7 Microtus agrestis, and 5 Sorex araneus from the same forest. 143 sera were obtained from these rodents: 114 (82%) had microagglutinating antibodies to the "Swiss agent".
mesh_terms: D000818:Animals; D000907:Antibodies, Bacterial / Q000032:analysis; D001096:Arachnid Vectors; D003411:Arvicolinae / Q000382:microbiology; D051379:Mice; D012281:Rickettsia / Q000276:immunology / Q000302:isolation & purification*; D013557:Switzerland; D013987:Ticks / Q000382:microbiology*
chemical_list: D000907:Antibodies, Bacterial
vernacular_title: Enquête épidémiologique dans un foyer naturel de Rickettsies à Ixodes ricinus du plateau suisse.