#18,364
While HPAI H5 has been spreading aggressively in American dairy cows over the summer, during the months of August and September the United States reported fewer than 100,000 birds lost to the virus in commercial poultry (see graphic above).
Canada, until this week, had gone more than 6 months without a reported outbreak.
Two months ago, in Something Winged This Way Comes, we looked at the start of the annual southbound fall migration of birds from their northern latitude summer roosting areas.
Migratory birds for Europe, the Middle East, and Africa spend their summers in Siberia, Mongolia, or China, while here in North America more than 200 bird species spend their summers in the Alaskan Arctic Refuge.
Although primarily comprised of North American birds, this area is also overlapped by the East Asian flyway, which may allow birds from Siberia and Mongolia to intermix with our migratory bird population (see USGS: Alaska - A Hotspot For Eurasian Avian Flu Introductions).
While we don't have a good handle on what viruses may have circulated in these remote breeding sites over the summer - or what reassortments may have occurred - we may find out in the coming weeks.
Both lulls now appear to have ended, as the United States has reported 3 major outbreaks (and 3 minor ones) since the 1st of October, involving > 3.4 million birds and British Columbia has reported 3 outbreaks in commercial poultry (numbers not provided) over the past week.
Notably, the large outbreak in Washington State has produced at least two confirmed human infections among farm workers (engaged in culling activities), and the CDC expects that number will rise.
Credit USDA
With the level of H5N1 in wild birds - and in the environment - expected to rise over the coming months, the USDA is reminding all flock owners (large and small) of the importance of biosecurity in defending the flock.
While poultry farmers are undoubtedly at a much higher risk, the CDC is also offering the following Advice for Pet Owners:
Pet Owners
If your domestic animals (e.g., cats or dogs) go outside and could potentially eat or be exposed to sick or dead birds infected with bird flu viruses, or an environment contaminated with bird flu virus, they could become infected with bird flu. While it's unlikely that you would get sick with bird flu through direct contact with your infected pet, it is possible. For example, in 2016, the spread of bird flu from a cat to a person was reported in NYC. The person who was infected [2.29 MB, 4 pages] was a veterinarian who had mild flu symptoms after prolonged exposure to sick cats without using personal protective equipment.
If your pet is showing signs of illness compatible with bird flu virus infection and has been exposed to infected (sick or dead) wild birds/poultry, you should monitor your health for signs of fever or infection.
How to prevent spread
As a general precaution, people should avoid direct contact with wild birds and observe wild birds only from a distance, whenever possible. People should also avoid contact between their pets (e.g., pet birds, dogs and cats) with wild birds. Don't touch sick or dead birds, their feces or litter, or any surface or water source (e.g., ponds, waterers, buckets, pans, troughs) that might be contaminated with their saliva, feces, or any other bodily fluids without wearing personal protective equipment (PPE). More information about specific precautions to take for preventing the spread of bird flu viruses between animals and people is available at Prevention and Antiviral Treatment of Bird Flu Viruses in People. Additional information about the appropriate PPE to wear is available at Backyard Flock Owners: Take Steps to Protect Yourself from Avian Influenza.
(Continue . . . )