A federal quarantine has been lifted for a duck farm near St. Catharines, Ont. where birds were confirmed in July with low-pathogenicity (“low-path”) avian flu.
The Canadian Food Inspection Agency has reported the quarantine was lifted effective Sept. 20, at the end of a 21-day waiting period after the commercial-scale farm was depopulated, cleaned and disinfected.
About 14,000 twelve-week-old ducks on the Niagara-region farm were euthanized and composted after an outbreak of low-path H5N2 avian influenza was confirmed there on July 8.
According to CFIA, the flu subtype in this case was of a North American lineage, and was a low-path version of a subtype seen in high-path outbreaks in Ontario last year and in British Columbia in 2014-15.
Low-path strains of avian flu aren’t considered as intense in terms of the illness caused in infected animals. However, low-path and high-path strains of H5 and H7 avian flu are all considered “notifiable” in Canada, meaning all cases must be reported to CFIA and are subject to control measures.
Trading partners such as the U.S. have previously put limits on imports of poultry and related products due to high-path bird flu outbreaks. Others, however, have been known to set up restrictions over a low-path outbreak, such as the low-path H5N2 cases at a Manitoba turkey farm in 2010.
In recent high- and low-path avian flu outbreaks, a three-month “enhanced” surveillance period has followed depopulation and disinfection at infected sites.
That surveillance period begins on the day the last infected premises in an outbreak completes its cleaning and disinfection — in this case, Aug. 30, according to CFIA officials.
If no new avian flu cases appear in the country over the three-month period, Canada may again declare itself free of notifiable avian flu at the end of that stretch. — AGCanada.com Network
CLARIFICATION, Oct. 6, 2016: A previous version of this article incorrectly stated the three-month enhanced surveillance period, after which Canada could again declare as avian flu-free, began at the end of the farm’s 21-day waiting period.