Understanding Highly Pathogenic Avian Influenza

Here are some facts about HPAI:

HPAI stands for Highly Pathogenic Avian Influenza. It spreads very easily among flocks, and has a high rate of mortality.

Avian Influenza (AI) is separated into two categories: Low pathogenic which has few visible symptoms (aka clinical signs) and a relatively low mortality rate, and Highly pathogenic which has a high mortality rate and is easily spread. Low Pathogenic strains can suddenly and without warning become highly pathogenic.

AI is spread from wild birds, via direct transmission or through exposure to their manure. It can be passed via contaminated footwear and clothing.

Wild birds, and in particular waterfowl, act as reservoirs for infection because they are usually less severely affected by the virus. The current outbreak is different in that it seems to also be highly pathogenic among wild bird species. If you’re seeing a larger number of dead birds, like ducks and geese, in public parks and spaces – this is why.

This particular strain has also been identified among bald eagles and red-tailed hawks, which means in addition to having an impact on our food sources, it is also having an environmental impact.

This strain landed on the East Coast in North America something like a year and a half ago and has been steadily working its way West before landing in BC around April/May. It moves with the migration of waterfowl, so that in the Fraser Valley for example, we saw a slow down of infections during late July and August, then saw a resurgence around mid September. Most recently something like 7 Poultry operations were shut down around Abbotsford and Chilliwack and there is an outbreak at a Popular local park which is ending up with the grizzly site of several dead birds, and other birds feeding on them.

What it means for your farm or homestead?

AI is a reportable disease, meaning by law if your farm or homestead has an outbreak, you are required to inform the proper authorities and your farm is put under quarantine. The agency that handles is the Canadian Food Inspection Agency (CFIA).
Once confirmed through lab testing, ALL of the birds on site and all poultry by-products such as eggs, MUST be humanely disposed of. This includes pet birds. There are NO exceptions.

Anyone entering or exiting your property must undergo strict biosecurity protocols including sanitizations of both persons and vehicles. This may include visitors to your residence as well. Additionally, anything moved off farm must also be decontaminated, and access to your farm must be limited to essential services only. All pets must be confined. You may also have to do wildlife and pest control in your area.

In addition to your farm, all poultry producers within a designated zone will also be quarantined and tested. In the case of confirmed HPAI, poultry on other farms within a km will also be culled as a precautionary measure – this part may have changed and is now only done in certain cases. They do however set up a Primary Control Zone which is a much wider area in which movement of poultry products is heavily restricted and monitored.
If you have close contact with any other producer: ie. You share equipment, you recently exchanged birds or by-products like eggs, they will also be quarantined.

You will be required to sanitize and decontaminate every building, tool, piece of equipment, and vehicle that is on your property. After a minimum of 14 days, your farm will be tested to confirm it’s been properly decontaminated. Once the re-infection or close proximity infection risk is believed to have passed, the primary controlled zone will be revoked and movement of poultry can resume.

For a farm, this can mean that your production capability is completely stopped for a significant period of time, while still having to pay employees for labour involved in sanitization of whole operation. In addition, you are now faced with the cost of having to replace all of your stock which is a major cost.

If you have chickens or poultry of any kind, you are encouraged to keep them in indoor enclosures like barns, or to confine them to enclosed runs that are not accessible to wild birds.

Why Should You Care if You’re Not a Farmer?

AI is Zoonotic, meaning it can be spread to humans (and from humans to other birds). AI is also responsible for causing other Influenza viruses to become zoonotic. Remember Swine Flu? We didn’t actually get it from pigs.

What we call Swine flu came from pigs maybe some hundred years ago, but then crossed the species barrier to infect birds. Once it existed in birds, it came into contact with an AI virus. When viruses infect the same host, they like to share genes, and one of AI’s favourite ones to share is the one that lets viruses jump the species barrier to humans.

This is a good time to also remember that low pathogenic strains of AI are known to suddenly become highly pathogenic, and that’s another gene they can share.

Fun fact – we name influenzas by the first species in which it was identified, not the species we actually got it from. Doesn’t stop it from having a devastating effect on farmers who farm that particular species.

Past outbreaks of AI in people have had a mortality rate of close to 50%. It spreads to people via exposure to infected animals. So far there have not been cases caused by consuming infected poultry however, it would be a good idea to make sure all your poultry is fully cooked.

The other reason it matters is because of the impact it will have on food prices and food security.

The farms being closed down are those helping provide poultry and eggs to stores. When they’re closed down, when the poultry is culled and the eggs destroyed, that lowers the overall supply that is available for consumption. Additionally, it’s not just that one producer who is restricted, but the ones in the surrounding area too.

It’s not just Commercial farmers who are affected either. People who keep chickens to supplement their own food supplies are at risk. In the early 2000s, a massive outbreak of HPAI in Canada led to a preventative culling of backyard chickens and spurred a movement of bi-laws banning ownership of chickens to reduce the risk to commercial operations.

What Can You Do?

Avoid unnecessary visits to farms.

I get it. I love going to farms and visiting animals. But right now, less movement through farms limits the potential for introduction of pathogens.

If you spot areas with lots of dead birds, report it to the City and/or CFIA so that they can be removed and disposed of in ways that limit the risk of transmission to other birds and to wild animals which can also be infected.  Try not to enter the area further if possible. Scrape and clean off your shoes to remove any possible manure and then disinfect your shoes with something like hydrogen peroxide. This helps limit the spread of the pathogen to areas where it might come into contact with other birds.

If you have backyard chickens, try and keep them confined to a run or an indoor area. Make sure they are not sharing water or feed with wild birds. Use a specific pair of shoes just for use near the chickens, and don’t wear them to other places. This helps prevent introducing pathogens to the areas where they might come into contact with your birds.

Understanding Highly Pathogenic Avian Influenza

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