Background: Recurrent cases of gastroenteritis occurred in a small hotel. The causative agent of disease could not be detected.
Material and methods: The cause and the source of the disease were established through epidemiological investigations and laboratory diagnosis.
Results: The causative agent of the disease was norovirus GI.3. Norovirus GI was detected in the water from the well and on surfaces at the hotel.
Conclusions: Both epidemiological investigations and laboratory diagnostics are needed in resolving epidemics. Continuous development of laboratory methods is important.