When you become infected with the virus that causes COVID-19, your immune system reacts in a number of ways. You may get symptoms of infection, which can vary depending on the particular strain. For example, a runny nose, headache and fatigue are common symptoms of Omicron.
This is a companion discussion topic for the original article at https://patient.info/news-and-features/do-you-get-better-covid-19-immunity-from-vaccination-or-infection