Here are a few take-home points from the night:
- EHD is a viral disease spread by biting midges. Only a couple of species of midges spread the virus. It requires the midges to spread it 90+% of the time (deer-to-deer transmission is rare). The midges are limited by climate and normally do not survive our winters. In recent years, the disease has been more and more prevalent further and further north. It is not clear whether this is due to climatic conditions or increased cold tolerance in the bugs. Bugs can travel large distances north on a gust of wind.
- In many cases infected deer die in 3-7 days (acute infection). They die in good body condition with severe hemorrhaging noticed internally. Multiple dead deer near/in water is common. Wide-scale losses of 25% of the population are common. Acute infection is the common form in herds that are not regularly exposed to the disease (chronic infection has different symptoms but I won't get into that).
- To date, only 2 confirmed deer in Ontario (bring on the hard frosts, baby)
- CWD is a prion, not a virus, and has very different vectors. Captive deer are a massive problem in North America and are the normal way this disease makes it way across the continent. Once it is in an area, massive-scale depopulation (cull every deer for miles) is the only hope of keeping it contained. The prion can remain active for years in soil.
The MNR presenter couldn't make it as she was quite sick so I delivered her presentation. I stole this from one of her slides, I hope she doesn't mind.