The average number of people falling ill per 100,000 was 487 last week, with above-average numbers of those affected in Tallinn as well as the Ida-Viru, Järva, Lääne, Rapla, Tartu and Viljandi counties.

The spread of the influenza virus has increased across all age groups, doubling among over 65-year-olds and increasing by 58% among children of the age of five or younger.

Estonia's young are the ones affected the most, with 52% of all lab-confirmed flu cases reported for children and youngsters up to the age of 19.

More than 80% of viral infections in Estonia at the beginning of this year are flu cases. As the Health Board reports, so far 539 A-type flu viruses and 14 B-type viruses have been identified. There are currently three main types of flu viruses around, the Health Board said.

According to preliminary data of health provider E-Tervise SA, 66% of flu patients turned to hospitals last week. Since the beginning of the current season, 689 people have been hospitalised, more than 60% of whom were children and youngsters up to the age of 19.

The larger hospitals report that some 40 patients required intensive care due to having contracted the flu. All of them, across all age groups, were risk group patients, the hospitals confirmed.