Indeed, and HIV is a “natural reservoir” disease that will continue to generate new strains even if we managed to eradicate it from the human population. The simian variant is just too compatible with us to ever really go away.
This actually raises an interesting question about potential diseases lurking in food sources. We now have 20/20 hindsight that eating an ape caused this and is therefore a bad idea. They obviously didn't know that when they chose to eat apes. There could be other such food sources that we don't know to be problematic yet. I am reminded of prions and mad cow, kind of a similar story.
The implications of food on longer term stuff like cancer will always be a hard thing to nail down but for serious diseases like this I don't think its currently a huge barrier.
Someone eats a monkey in rural Cameroon or Congo, and 10 years later they and their sexual partners have their immune system collapse. Will they know the connection?
Some sources say that happened circa 1910. It wasn't identified until the 80s. In the meantime there were some bunk theories tied to homosexuality, drug use, or poverty as the root cause.
I have heard that prion diseases can have even longer periods before they surface after exposure.
We didn't identify any retroviruses until the late 70s, we didn't know to look for them. That's different.
The first peer reviewed paper on human retroviruses wasn't until 1984.
https://retrovirology.biomedcentral.com/articles/10.1186/174...
In other words, it can take a long time to notice the correlation. I don't think it's much of a stretch to guess that there could be other such correlations, present and future, that have not been discovered or will take some time to discover.
It's getting harder. Privacy protections mean this type of analysis across hundreds of millions of records isn't really possible anymore. Without hundreds of millions of records, identifying "people who drank milk from Mr Smiths farm in 1969 were 200% more likely to get parkinsons 45 years later" couldn't be done.
Yet if Mr Smiths farm had cows with some as-yet unidentified prion disease, this is the only way we'd find it.
You think we have LESS data now than we did in the past?
We have more than ever, and easier ways of collecting data than we have ever had.
As soon as you stick the data through an algorithm without getting permission from everyone in the dataset, you're getting put in prison for GDPR violations. Have fun getting consent from 100M people with only their postal address from 50 years ago.
(1) Public Health Exemption Legislation
(2) Use the NSA/GCHQ to get the data, run the analysis and once you know the answer do parallel construction with a much smaller, legally available dataset.