to respond to the spike protein. When you get the virus, your body teaches itself how to respond to the spike protein. Of the 30,399,372 positive cases in the United States since the beginning, there have been a total of 11 verified cases where an individual tested positive twice as separate actual occurrences. You hear people talk about having it twice, or friends having it twice, but find out if they actually tested positive via a PCR test at least 90 days apart. You get a lot of "I know I had it but didn't get tested comments."