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An 89-year-old Dutch woman died after being reinfected by the coronavirus. It would be the world’s first case of fatal outcome from the second infection. The woman, El Mundo reports, was being treated for Waldenstrom’s macroglobulinemia, a rare type of cancer. Earlier this year she was admitted to the emergency room with a high fever and cough. After testing positive for coronavirus, he made a full recovery after 5 days. Almost 2 months later, and just two days after a new cycle of chemotherapy, he again had a fever, cough and respiratory problems and tested positive for the coronavirus again. On the eighth day of hospitalization, his condition worsened and he died 2 weeks later.
Cases of reinfection in the world
The analyzes carried out on the woman confirmed that the genetic makeup of the virus was different in each of the two infections. To date, approx. 23 cases of reinfection around the world, sometimes with better results and sometimes worse than the first time. Precisely these days the official publication in the scientific journal Lancet from a study on the second documented case of reinfection in the world (the first in the US) reported in August (we had discussed it who). He was a 25-year-old from the state of Nevada who became ill for the first time last April after suffering from a sore throat, cough, headache, nausea and diarrhea. The boy, who recovered towards the end of that month, fell ill on May 31 with the same symptoms, which in the second case forced him to enter the hospital for respiratory failure. This is the other peculiarity of the case (the worst course), in addition to reinfection.
What do we know
Commenting on the study describing the story of the 25-year-old in Lancet, an editorial by Akiko Iwasaki, Yale Professor of Cellular and Developmental Molecular Biology, which assesses what we know so far about reinfections by answering four questions.
The first is if reinfections occur due to a poor antibody response. Of the four official cases of reinfection – writes Iwasaki-, that is to say with genomic sequences analyzed both after the first infection and after the second and accompanied by official studies, none presented immunodeficiencies. Currently, only two people had serological test data related to the first infection, and due to the variety of kits adopted in all countries of the world, it is impossible to compare the results with each other. Furthermore, writes the expert, antibody levels are highly dependent on the time elapsed since exposure to the virus. There are not enough data and studies.
Second question: does immunity protect an individual from the disease in case of reinfection? The answer “not necessarily”, given that at least two reported cases (from Nevada and Ecuador) had worse disease outcomes in the second reinfection than in the first. It is important to bear in mind – the doctor warns – that cases of reinfection are generally reported when they are symptomatic, so we do not know how often reinfection occurs among people who have recovered. We are probably underestimating the number of asymptomatic reinfections. As for why there is sometimes a more serious illness, more research is needed on pre-existing immune responses and on the viral load recorded in both infections.
Third point: does getting infected with viral strains of different characteristics mean that we will need a vaccine for each type of viral variant? Although differences in the sequence of the viral genome are an excellent way to really know if an individual is reinfected, or if it is a virus still latent in the body (and therefore a relapse), this does not indicate that the second infection is due. to an immunodeficiency. There is currently no evidence that a significant variant of SARS-CoV-2 has emerged. For now, one vaccine will suffice to confer protection against all circulating variants.
Does immunity prevent transmission from those who are reinfected? In some cases of reinfection, it is believed that the infectious virus may have lodged in the nasal cavity. Therefore, reinfection cases tell us that we cannot rely on antibodies to signal herd immunity. People who are infected a second time can also be contagious. Herd immunity, Iwasaki writes, requires safe and effective vaccines and strong implementation of vaccination campaigns.
October 13, 2020 (change October 13, 2020 | 17:10)
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