A healthy young woman who developed antibodies against the new coronavirus (Covid-19) after being infected in the first wave of the pandemic was reinfected in September, De Standaard newspaper reported on Saturday, based on a Belgian case study that is still to undergo a peer review.
This could indicate that the number of antibodies drops relatively quickly after infection, virologist Kevin Ariën of Antwerp’s Institute of Tropical Medicine (ITG) commented.
This is probably the first documented case in the world in which it had been noted that the infected person’s immune system had been intact, and their immune response had been good, after a first infection.
“In previous reinfection cases, the immune response had not been measured or was not fully functional,” Ariën said. “This case makes one think, in any event, of the other coronaviruses, whether SARS or MERS. There, too, we saw immunity drop quickly below a ‘critical threshold.’”