ST. PETERSBURG, March 21 (Xinhua) -- A surge of influenza, including swine flu and Hong Kong flu, was detected in Russia over the past week.

Interfax reports that the Russian Research Institute of Influenza confirmed 557 cases of swine flu in 45 cities and 360 cases of Hong Kong flu in 44 cities across Russia during the period of March 12-18.

In general, the epidemic threshold of influenza is exceeded by about 25 percent in the country.

The peak flu incidence rate was in the North-West Federal District of Russia, where the weekly threshold was exceeded by 43 percent.