They're carried by different mosquitoes in different habitats and differ sharply in severity. West Nile virus is spread mainly by Culex mosquitoes and is usually mild, while Eastern equine encephalitis comes from swamp-breeding species and is far rarer but much more dangerous. Both occur in Michigan.
People tend to lump West Nile virus and EEE together as “the mosquito diseases.” That’s right, but there is also a big difference that’s worth talking about and knowing about.
West Nile virus is more common. You can thank the Culex mosquitoes for that, they’re the common house mosquitoes that chase you around at dusk and pool in stagnant water like clogged storm drains. The virus lives in birds, and the mosquitoes pick it up and transmit it to people. About eight in ten infected people don’t show symptoms. Most of the rest show flu-like symptoms. A very small remainder develop serious neurological illness, with older adults being at the highest risk. It shows up in Michigan most summers.
EEE is rare but scarier. It comes along with Culiseta melanura, which is a mosquito that breeds in hardwood freshwater swamps. It feeds almost entirely on birds, only rarely biting people directly. It’s the “bridge” mosquitoes (certain Aedes and Coquillettidia species) that pick it up and carry it to people and horses. It tends to break out on swampy wetlands and cluster in specific regions, including parts of southwest and central Michigan. It’s rare, but about a third of people who develop the brain inflammation it causes die, and many survivors are left with lasting neurological damage.
You can’t easily tell mosquitoes apart by looking at them. So the practical response is to try to clear as many of them as you can from your property, and use personal repellents with DEET or picaridin when that’s not possible.
If you're tired of the guesswork that comes with mosquito season, Mosquito Squad of Fenton - Brighton can help. Mosquito Squad helps cut standing water sources and reduces the mosquitoes around your home, helping protect your family with up to 90% reduction in mosquito activity on a recurring 21-day cycle.
