Charlotte Thålin, a doctor and researcher responsible for the study at Danderyd Hospital in Stockholm, explained that when antibodies decline, so-called memory cells are still retained in the body:
When we encounter the virus again, these memory cells start producing antibodies again and we also have T-cells that work very closely with the B-cells, developing the antibodies. So detectable antibodies is an important but small part of the complex immune system."
Thålin added that there is still much to be learned about how Covid-19 affects the immune system but she believes there are reassuring signs that those who have fallen sick are unlikely to be reinfected soon after a first bout with the virus, adding that the results are corroborated by an earlier Icelandic study.
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