BRUSSELS, Jan. 22 (UPI) -- Influenza activity continued to increase across Europe during the second week of January with reports of severe cases in some countries, officials say.
The European Center for Disease Prevention and Control in Brussels said in its Weekly Influenza Surveillance Overview 19 European countries reported an increasing trend of influenza transmission.
Medium or high intensity of influenza transmission was reported by 14 countries. High transmission occurred mostly in the northwest of Europe in Norway and Iceland, the report said.
Twelve countries reported low intensity transmission and 12 medium intensity.
The Czech Republic and Slovenia reported medium intensity for the first time this season, while 12 countries have been reporting medium or high intensity for at least two consecutive weeks. France and Italy have been reporting medium intensity for four consecutive weeks, the report said.
Only Bulgaria reported no activity.
Virological surveillance for the period shows of the 1,238 sentinel specimens tested, 42 percent were positive for influenza virus. This relatively high percentage is similar to what was seen in the two previous weeks, the report said.
Of influenza A viruses subtyped, 48 percent were H3N2 and 52 percent were H1N1. The virological pattern seen in Europe was different from that reported in North America, where H3N2 viruses were dominant.