What Do Sunspots Have to Do With Pandemics Like Influenza and Covid-19?

As Covid-19 is dominating this respiratory illness season, the flu season has disappeared. It turns out that the flu virus does not conform to many known properties of infectious diseases. It can appear simultaneously around the globe and disappear just as quickly. Additionally, there may be a relationship between Covid-19 and influenza activity as well. Lastly, there is a link to solar activity, sunspot activity, and pandemics that I explore in this post.