Just as a reminder, in 2021 there were close to 250 million estimated malaria cases worldwide, with an estimated ~600.000 deaths according to WHO, so it is very much a concern for the world even though it was eradicated in the USA
By comparison in 2021 there were twice as many COVID deaths.
[0] https://emergency.cdc.gov/han/2023/han00494.asp
[1] https://www.cdc.gov/malaria/about/history/elimination_us.htm...
Also the US military warned years ago that increased climate temperature would bring back malaria to the states, and here we are.
It's absolutely coming back to the US. Mosquitos are moving north to stay in their optimal temperature range as the climate warms.
edit: My wife saw my comment and got annoyed that I listed the wrong subspecies. Updated to include Anopheles Darlingi.
So the warmer the states get, the warmer the land south of the states get. More and more mosquitos survive winters closer to the states, and so smaller travel distance.
But based on what you just said it seems that understanding is not actually how it works?
Temperature impacts mosquitos in several ways that change their effectiveness as a vector for disease.
The temperature during egg/pupa/larva stages impacts adult body size and fitness of the mosquito. That in turn tends to impact total lifespan.
A change as small as 2 to 4 degrees C can add or remove more than a week of lifespan for a mosquito (huge change, the average lifespan is 10-14 days), and the longer a mosquito is alive, the more likely it is to become a vector for malaria (and other diseases). For malaria in particular - the life cycle of the disease means the mosquito usually needs to make it at least 10 days to become a vector.
Throw on top that changes in temperature can change the feeding habits (shift them in time to make mosquitos more likely to feed when humans are out) and that parts of the southern US are now considered viable habitat for these subspecies and you get Malaria.
They do still need to interact with an animal/person carrying malaria during their adult stages - and the general strategy in the US is still to contain and treat those carriers.
We just expect it to get much more expensive as these mosquitos become more fit for our region.
Can we use bats or nematodes to fight this return?
I spray my lawn with beneficial nematodes. I saw some small decline in the number of mosquitoes born in my yard but it doesn't stop mosquitoes from surrounding areas. My next move is to install a bat house on my house.
Her advice:
- Remove standing water anywhere you can
- Use nets/screens on open windows/doors to reduce access
- Avoid outdoor activities at dawn/dusk when they are most likely to feed
- Don't plant bushes near outdoor seating (apparently they hide there during the day, but will choose to feed outside normal hours if it's convenient)