Around 30 people became ill from a party of some 200 diners who gathered for a private function at a Helsinki restaurant. Almost all those affected were diagnosed as suffering from the same bacterial infection.

The environmental centre of the City of Helsinki has examined the incident by means of a questionnaire together with the help of samples taken by the National Institute for Health and Welfare (THL). However, no food with the offending salmonella bacteria has been detected.

According to Riikka Åberg from the environmental centre, the precise cause of such an epidemic is rarely determined. Final results will be ready next month when the questionnaire data is finally known.

Around 300 cases of salmonella are detected in the Finnish capital annually, of which around one in ten is of domestic origin.

A salmonella epidemic was last reported in Helsinki at the end of last year when over ten people fell ill after eating at the same luncheon diner.