The first two vaccines “out of the gate” in the U.S. were developed by Pfizer/Biontech and Moderna. They both contain mRNA and underwent rigorous scrutiny in clinical trials before receiving Emergency Use Authorization.
Question: Can someone who has already had COVID-19 get reinfected?
Answer: Yes. In fact, reinfection has been documented in a handful of persons in different countries. The first was in Hong Kong. It is unclear how often reinfection occurs, but it is expected to be uncommon. Scientists confirm reinfection by comparing the genetic composition of the SARS-CoV-2 virus found at different times in the individual and showing they are not the same.
Remember “COVID-19 immunity passport”? That is the idea that once someone has had COVID-19, they essentially become immune and can never have it again. We now know that is not true for everyone. The well-documented instances of COVID-19 occurring more than once in the same person in Hong Kong, Europe, Ecuador and USA have proven that universal immunity passport for COVID-19 is a myth.
We should not be shocked that some people can have COVID-19 more than once. This is well known to occur with many other infections. One question that still needs to be answered is whether/how previous infection affects the severity of COVID-19 if it hits the same person again. Scientists are also trying to understand whether reinfection affects how infectious a person is.
No cause for alarm. Nothing about reinfection after having COVID-19 is unheard of. We should, however, continue to be good public health citizens, and practice good habits that limit infection and spread of not only COVID-19, but many other respiratory viral infections.