The study reports Parkinson’s Disease occurring 10-15 years after an influenza infection. The study supports getting flu shots annually, which may also be cross-protective to some extent against Covid-19. The second important finding confirms chronic disease can develop decades after acute infection. Finally, the study raised the issue of the overall infectious burden caused by multiple chronic infections.

We must start identifying the most dangerous acute infections early, including influenza, intracellular pathogens, and parasites; and offer treatments that are available early in the course of the infection, before the acute infection becomes a chronic disease.

https://jamanetwork.com/journals/jamaneurology/article-abstract/2785029