A November report to the World Organization of Animal Health confirmed four outbreaks of Newcastle disease (paramyxovirus 1) in flocks in Poland, Two of the outbreaks involved 45,000 laying hens in Topilek and 28,000 in Bojary, both in Podlaskie Voivodeship (Province) in the northeast quadrant of the nation, adjoining Lithuania. Two small farms in the locality were also infected. The last outbreaks of Newcastle disease diagnosed in Poland occurred in 1971 attesting to the efficacy of vaccination.

According to the WOAH report, flocks were not vaccinated against Newcastle disease.  The only other outbreak of this infection reported during the past year comprised two cases in Denmark where farmers do not routinely vaccinate flocks against Newcastle disease contrary to universal practice.