The first documented Coronavirus reinfection was reported in Hong Kong on August 24th, 2020. Experts say this finding was not unexpected, “especially given the millions of people who have been infected worldwide”. While there have been many presumed cases of reinfection, this case was the first to be confirmed.
Interestingly, the 33-year-old man’s second infection was completely asymptomatic. This suggests that while the prior exposure did not completely prevent reinfection, his immune system did prevent the disease from getting worse. Akiko Iwasaki, an immunologist at Yale University, explained that, “it’s kind of a textbook example of how immunity should work.”
However, this finding does also present challenges. Several viruses, such as common cold viruses, often cause repeated reinfections in a short amount of time, which makes it difficult to produce vaccines. Public health experts had hoped that the new coronavirus “might behave more like its cousins SARS and MERS, which seemed to produce protection lasting a few years”. Unfortunately, since one can be reinfected with COVID-19 so quickly, it is clear that “in order to provide herd immunity, a potent vaccine [needs] to induce immunity that prevents both reinfection and disease” – a challenging combination, for sure.