How long and how strong is immunity after having COVID-19? There are many questions about whether or not people can be protected against reinfection. Previous studies have suggested there is a big decrease in antibodies (which promote immunity) over time. Does this mean that immunity to the disease quickly falls after infection? A recent study of 12,500 healthcare workers from the United Kingdom suggests that immunity six months after infection protects people as well as the Pfizer vaccine. Now, new research from New York studied 87 individuals who had the virus and measured antibodies in their blood at 1 month and 6 months after infection. Researchers found that while levels of certain antibodies may decline, the immune system should still be able to protect you from COVID-19 for at least six months after COVID infection. So if you have had COVID-19, at least in the short term, you are unlikely to get it again. This is good news.