[Eric Coffey]

Originally Posted by RWebb

Here Eric - do some reading

https://www.annualreviews.org/doi/abs/10.1146/annurev.med.51.1.407

Please cite any passage therein that states the 1918 pandemic "came roaring back in January because people stopped wearing masks". I'll wait...

Until then, I'll let you in on a little secret: Most respiratory viruses "come roaring back" during the colder months, regardless.
This has nothing to do with masks, and more to do with seasonal climatic changes (specifically the reduction in RH/AH).