Over the past nine months the South West of the USA is fighting against the velogenic viscerotropic Newcastle disease with relative success. New outbreaks have been found even further away from the initial source. An update.

For the past 20 years intensification of the poultry industries in the EU and North American and expansion in Asia, the Middle East and Latin America, have led to the emergence of new diseases and more virulent forms of infections that were considered to be under control in the mid-1970's.

Vaccination is one tool that is frequently used to control or eliminate infectious disease organisms. Each poultry farm is unique and has its own set of variables that need to be considered when designing an effective and economical vaccination programme.