A total of 135 people in the Krasnoyarsk Territory in East Siberia have been diagnosed with yersiniosis, a bacterial stomach infection, as of Wednesday morning, a spokeswoman for the local consumer safety regulator said.

Of the 135, thirty four children and four adults remain in hospital.

Yersiniosis is an infection contracted through eating undercooked food or liquids contaminated by the bacteria. The disease, which usually affects young children, typically develops from four to seven days after exposure and may last up to three weeks.

Measures to prevent the spread of the disease have been introduced in all the region's childcare facilities. Meals containing raw vegetables have been banned; raw cabbage is considered a likely cause of the outbreak.

Children infected with yersiniosis usually recover within a few days without treatment, but complications including the spread of the bacteria to the bloodstream can occasionally occur.