- Researchers have long believed simple infections could lead to long-term problems.
- But solid scientific evidence has only been accumulating in recent years, experts say.
- Understanding how the immune system overreacts and is reinforced could lead to better treatments.
In most people, norovirus causes a few days of misery spent in the bathroom and then is quickly forgotten. Epstein-Barr virus can pass without any indication at all. And many people shrug off COVID-19.
But a growing body of research suggests that in some unlucky few, the immune system overreacts to these seemingly minor insults, leaving years or even a lifetime of symptoms.
