My impression at the moment is that all the claims that P1 causes loads of reinfections depend on this one study of Manaus blood donors that found 75% prior infection rate. Other lines of evidence (e.g. testing neutralising antibodies) suggest that P1 is more like the UK variant B1.1.7 - more infectious and more lethal but less immune escape than the South African B1.351 variant.
Now one of these viewpoints must be wrong, and I’m inclined to believe it’s the blood donor study that’s wrong. Beyond usual worries that blood donors might not be a random sample, apparently people donating blood were also told their COVID-19 antibody status, so people who thought they had been infected might have been incentivised to donate blood. There’s also a different study ( SARS-CoV-2 antibody prevalence in Brazil: results from two successive nationwide serological household surveys ) which finds 14% prevalence in June, compared to 66% from the blood donor study.
Caveat: I haven’t been following this super closely so may well have missed some relevant results. I also haven’t looked into the credibility of the second prevalence study at all.
My impression at the moment is that all the claims that P1 causes loads of reinfections depend on this one study of Manaus blood donors that found 75% prior infection rate. Other lines of evidence (e.g. testing neutralising antibodies) suggest that P1 is more like the UK variant B1.1.7 - more infectious and more lethal but less immune escape than the South African B1.351 variant.
Now one of these viewpoints must be wrong, and I’m inclined to believe it’s the blood donor study that’s wrong. Beyond usual worries that blood donors might not be a random sample, apparently people donating blood were also told their COVID-19 antibody status, so people who thought they had been infected might have been incentivised to donate blood. There’s also a different study ( SARS-CoV-2 antibody prevalence in Brazil: results from two successive nationwide serological household surveys ) which finds 14% prevalence in June, compared to 66% from the blood donor study.
Caveat: I haven’t been following this super closely so may well have missed some relevant results. I also haven’t looked into the credibility of the second prevalence study at all.
These are helpful considerations to highlight, thank you.