RECENT INFLUENZA-A (H1N1) INFECTIONS OF RIGS AND TURKEYS IN NORTHERN EUROPE

The most recent introduction of an avian influenza A virus without rea ssortment into mammals occurred in 1979 when H1N1 strains could be iso lated from diseased pigs in northern Europe. This newly introduced avi an virus formed a stable lineage in pigs and, in the meantime, spread all over Europe. In 1991 highly pathogenic H1N1 strains closely relate d to a contemporary swine virus were isolated from turkeys of a breedi ng farm near Bremen, Germany, Outbreaks in several farms in Germany, F rance, and the Netherlands indicate that the ''avian-like'' swine viru ses can easily be reintroduced into an avian population causing severe economical losses. (C) 1994 Academic Press, Inc.