According to a submission by authorities in Poland to the WOAH, approximately 70 cases of cats with neural signs and mortality have yielded H5N1 avian influenza on viral assay, presumably by PCR.  Most of the cats were feral and it is believed that infection was acquired from predation of wild birds.  The number of cases diagnosed and the fact that infection was confirmed in cats from diverse areas (Gdansk, Lublin, Poznan)  indicates the extent of H5N1 influenza in the areas where cases have occurred.  The epidemiology of the clusters is under review by veterinary authorities in Poland including the possibility of direct transmission among colonies of feral cats. The consequences of zoonotic transmission are self evident.. 

This report follows a December 2022 diagnosis of H5N1 in a semi-domesticated cat in France with access to a duck farm.  Six cases of avian influenza have been diagnosed in U.S. domestic cats in addition to wild felines including free-living cougars and large cats in zoos.

Dr. Sylvie Briand of the World Health Organization stated, “We take the risk from this virus seriously and we urge heightened vigilance from all countries.”