Rapid Propagation of Norovirus Gastrointestinal Illness Through Multiple Nursing Homes Following a Pilgrimage

Abstract
Reported here is an outbreak of gastroenteritis due to Norovirus infection that affected at least 450 persons from nursing homes and similar institutions in Switzerland during and after an organised pilgrimage to Lourdes in France. The outbreak was characteristic of direct person-to-person transmission, with the primary cases occurring in the hospital that harboured some of the pilgrims in Lourdes.