The participants in the study were representative of a demographic and geographic mix, and the results could be a game changer for the global response to Covid-19.
Lead researcher Eran Bendavid said: “Addressing Covid-19 is a pressing health and social concern. To date, many epidemic projections and policies addressing it have been designed without seroprevalence data to inform epidemic parameters.”
If applied to the whole county and not just those in the study, it would mean that between 48,000 and 81,000 people are infected in Santa Clara, and that’s “50- to 85-fold more than the number of confirmed cases”, said Bendavid. This implied that “the infection is much more widespread than indicated by the number of confirmed cases. Population prevalence estimates can now be used to calibrate epidemic and mortality projections.”
Madhi told Times Select: “This data fits with other recent reports that indicate that as many as 50% to 80% of people infected with SARS-CoV-2 would be asymptomatic.”
Such people “would not have been considered for testing even in places where a symptomatic approach to identify suspected cases was effectively implemented”.
“So, while it shows that infection is more common than we previously realised, the good news is that it also indicates that the vast majority – more than 95% – of individuals that are infected will either have no clinical signs of illness or only mild illness.”