An 89-year-old woman from the Netherlands died after contracting COVID-19 twice, according to researchers, and this is believed to be the first reported case of death due to the reinfection of the virus in the world.

In late August, the first ever case of COVID-19 reinfection was recorded in the world as a 33-year-old man from Hong Kong tested positive for the virus for the second time, four months after his initial recovery in April. This raised concerns among people about how long immunity and antibodies can last in individuals who already had the viral infection once. Since then, there have been numerous other cases of reinfection across countries. According to researchers, the elderly Dutch woman, who had Waldenström's macroglobulinemia, a rare type of cancer, was being treated with B-cell-depleting therapy when she tested positive for COVID-19. She reportedly had a fever and severe cough and went to the emergency room, where she tested positive for the virus. 59 days after the initial diagnosis, the woman developed symptoms of COVID-19 yet again and a test revealed that she had contracted the virus for the second time.

Researchers reportedly said, "Findings suggest that the patient was infected by SARS-CoV-2 on two separate occasions by a genetically distinct virus. Thus, previous exposure to SARS-CoV-2 might not guarantee total immunity in all cases. Our patient was immunocompromised, because of Waldenström's macroglobulinemia treated with B-cell-depleting therapy, resulting in a declined humoral immunity. However, it was shown that B-cell-depleting therapy does not necessarily result in life threatening disease, suggesting that the innate immune response and T-cell immunity can be sufficient to eliminate SARS-CoV-2."

Regarding reinfection in people, in general, Corey Smith, head of translational and human immunology at the QIMR Berghofer Medical Research Institute in Brisbane, earlier mentioned in a statement that it would be difficult to identify people who have been reinfected if they did not show any symptoms. "Because he (the Hong Kong patient) showed no symptoms on the second infection, it is likely that, although the virus has managed to establish infection, his memory immune response has likely prevented any symptomatic disease. This does suggest that natural infection may provide protection against disease, but not reinfection," Smith stated.