In a post on the California Department of Food & Agriculture (CDFA) website, California state veterinarian Dr. Annette Jones noted Dec. 23 that over the month of December, virulent Newcastle disease (VND) cases have increased in southern California "because people have violated the CDFA VND regional quarantine by moving infected birds or contaminated equipment and secondary spread to neighboring flocks."

She said there are now 20 new cases under investigation, all linked to the recent Bloomington, Cal., area outbreak. Most of the cases are in San Bernardino County, with two in Riverside County and one in Los Angeles County. Backyard flocks as well as retail pet/feed stores are involved, Jones said.

Based on phylogenetic analysis and epidemiologic studies, Jones said CDFA understands "how the disease spreads in southern California. This highly contagious virus has been spread when people move exposed birds or equipment or when people carry the virus to their own unfortunate flock on their hands and feet. It moves long distances as people illegally move birds or equipment. When introduced to a new area, it is amplified, as the previously uninfected poultry succumb until the environmental virus load is so great [that] the outbreak spreads from yard to yard. Exposed poultry around a newly infected flock are the 'virus amplifiers,' particularly just before they show signs of disease."

Jones emphasized that birds can spread the disease before they show symptoms, so the only way to stop VND is to not move birds — period — if they are in the CDFA regional quarantine area.

As a reminder, Jones said over the course of the current outbreak, which started in May 2018, the disease was spread from San Bernardino to Los Angeles and Riverside counties and beyond, leading to widespread highly infected areas, infected poultry farms, the death of more than 1.2 million birds and significant financial and emotional strain on poultry owners and disease control agencies.

Jones said state and federal disease control officials need everyone's help to stop the spread of VND and end the outbreak. Specific actions that can be taken to protect poultry are listed on CDFA's VND website in biosecurity videos, guidance documents and links, but general keys to success include: