Passsenger Pigeons would probably be the most useful deextinction as they could be a major low cost food source. In fact when they existed in swarms, indentured servants sometimes had contract saying they could only be fed PP a certain number of days a week. Unfortunately breeding the swarm size that would allow mating behavior would not be easy.
Regarding Covid and Spanish Flu, God help us if Spanish Flu gets loose. It killed 50 million people in 2 years. I think Covid has only killed about 6 million, and that is with a world population multi billions of people more these days. Of course we have more experience with flu vaccine, so might get one more quickly, but distribution would be much harder as the SF spread really fast, I could imaging as many as 200 million dead in a year or two. Meanwhile if they don’t get on top of Monkey Pox with serious contact tracing, that could also become endemic, and it should not as it spreads less easily.
The five years of “Spanish Lady” influenza (this is from the Gina Kolata book) shows that the 1916 season saw the start of it, 1918 was the peak, and the trailing years were ‘19 and ‘20. There was something peculiar about that particular strain, as those who were about to die hemorrhaged in their lungs.
Another Kolata find, those who had survived the worst flu strain of the 1890s already had immunity from the Spanish Lady, never even got the sniffles.
The reason so much effort is put into annual innoc’s for flu is to keep the mortality down. In the US, over the ten years from 2010 to 2020, the lowest was in 2011-2012 (12,000) and the worst two (2014-15, 2017-18) around 50,000 fatalities. Average is somewhere around 30,000 a year in the US, and worldwide estimates range from 294,000-518,000.
I’ll go way out on a limb here and suggest that the US, with perhaps 5 percent of the world’s population, has a much better system of dealing with influenza than most of the world, so that these world figures suffer from severe underreporting. It wouldn’t surprise me to learn that A) annual worldwide flu fatalities are north of a million, or B) that geography, jet stream, human travel etc tend to disproportionately funnel the bug into North America from its Chinese reservoir/homeland.
Ebola (the bad outbreak in West Africa happened 2013/4–2016, when the Kenyan-born muzzie was in office), and (it sez here) less than a dozen in the US were treated for it, and two died. Worldwide, something like 11K died, mostly in western Africa.
Here’s a group trying to recreate the Passenger Pigeon:
https://reviverestore.org/about-the-passenger-pigeon/
1918 Spanish Flu has been reconstructed:
https://www.cdc.gov/flu/about/qa/1918flupandemic.htm
IIRC “Mother Abigail” who once posted here said that cytokine storms were a factor in the lethality of that flu. Hybrid human-animal flus can provoke cytokine storms and 1918 was an H1N1 virus mixed with avian flu.
Cytokine storms may also have played a role in the lethality of the original Covid strain. It can cause multiple organ failure and death.
“Meanwhile if they don’t get on top of Monkey Pox with serious contact tracing, that could also become endemic, and it should not as it spreads less easily.”
Smallpox vaccines are supposedly effective against Monkey Pox. Unless we quit routinely vaxxing for smallpox there shouldn’t be a lot of risk in this country.