The number of children hit by a relatively rare infection in the east Siberian city of Krasnoyarsk has risen to 49, a spokesperson for the city's health department said on Sunday.

It was reported on Saturday that 46 children from the Solnechny summer camp were hospitalized with the symptoms of yersiniosis, an infection contracted through the consumption of undercooked meat, milk, water or vegetables contaminated by the bacteria.

Yulia Kryukova said more cases could be expected until June 26, as the incubation period for the disease is seven days.

Kryukova said police were inquiring into possible violations of sanitary rules at the summer camp.