Current Long-COVID Statistics Are Missing the Background Prevalence
Pinpointing the true estimate of long-Covid prevalence from asymptomatic, non-severe, and severe Covid-19.
In one of the most extensive and latest long-Covid meta-analyses to date, scientists Chen et al. at the University of Michigan School of Public Health, U.S. synthesized data from 34 studies and computed that the global prevalence of long-Covid stood at 43% of Covid-positive cases. This number has been cited in various news outlets covering long-Covid.
If long-Covid prevalence is really 43%, that means over 180 million people already have or had long-Covid. (Covid-19 cases surpassed 445 million, with over 6 million deaths, as of early March 2022.) That also means the chance of developing long-Covid is almost 50% if we tested positive for Covid-19. But such long-Covid prevalence is likely overestimated. Let’s see why.
What meta-analyses show
(1) In one early meta-analysis, Lopez-Leon et al. identified 15 studies on long-Covid — defined as having at least one symptom persisting for 14–110 days after SARS-CoV-2 infection — in the literature before 1 January 2021.
Harmonizing the studies’ data showed that 80% of 47,910 Covid-19 cases developed…
