A study of hundreds of thousands of people across England suggests immunity to the coronavirus is gradually wearing off – at least according to one measure.
“This is consistent with evidence that immunity to seasonal coronaviruses declines over 6 to 12 months after infection and emerging data on SARS-CoV-2 that also detected a decrease over time in antibody levels in individuals followed in longitudinal studies,”
The results also confirm earlier studies that showed that people who did not have symptoms of Covid-19 are likely to lose detectable antibodies sooner rather than those who had more severe infections.
Still, not enough is known to determine if antibodies provide any effective level of immunity to Covid-19, or how long people may be immune to reinfection with the coronavirus.
“This very large study has shown that the proportion of people with detectable antibodies is falling over time,” Helen Ward, who is on the faculty of medicine at the school of public health at Imperial College London, said in a statement.
“It is also important that everyone knows what this means for them — this study will help in our fight against the virus, but testing positive for antibodies does not mean you are immune to Covid-19,” Bethell said in a news release.