An egg production farm in Sweden housing 5,000 hens was depleted following a diagnosis of Newcastle disease.  The affected flock showed a sharp decline in production and abnormal shells with the diagnosis made before mortality was evident.

The flock was depopulated, and a surveillance zone was established over a six-mile radius of the affected farm.

It is noted that Sweden does not allow vaccination against Newcastle disease. This is contrary to almost all industrialized and developing nations.  The loss of birds and their production is totally avoidable given effective immunization applying a range of available safe and effective vaccines.