Report on the first two years of the Czechoslovak Influenza Centre.

The Czechoslovak Influenza Centre, which was set up in 1956, is attached to the Institute of Epidemiology and Microbiology at Prague and is supported in its activity by 15 virological laboratories situated in various parts of Czechoslovakia, which perform serological investigations of influenza and virus isolations.The first isolations of A2 influenza viruses in Czechoslovakia were made towards the end of May 1957. At the end of that year and early in 1958, B viruses were also isolated in several regions of Czechoslovakia, although the A2 viruses were more frequently encountered. The newly isolated B strains differed from those circulating in the country five years previously, and were added in 1958 to what had been a monovalent A2 vaccine.Favourable preliminary experiments were made in 1957-58 with the use of immune horse serum for influenza prophylaxis.The Czechoslovak Influenza Centre has taken part in an international investigation of animal sera (largely horse and swine) for the presence of influenza antibodies. In this work, use has been made of the virus A-equi/Praha/56, which was isolated by workers from the Centre.