ABOVE: © ISTOCK.COM, ILZE KALVE
Earlier this month, Spain published the results of a country-wide seroprevalence survey, which tested 60,000 residents for antibodies that suggest they had already been infected with—and thus may be safe from a future infection by—SARS Cov-2, the virus that causes COVID-19. The survey estimated that about 5 percent of the country’s population had been exposed to the virus, varying from 1.1 percent to 14.2 percent between regions of the country. Unfortunately, this means almost all of the population is still at risk.
“We have not been surprised” by the results, Salvador Illa, health minister, said at a news briefing earlier this month, according to Reuters. “There is no herd immunity in Spain.”
Seroprevalence surveys for anti–SARS-CoV-2 antibodies have faced considerable criticism from scientists, in part because the tests themselves have varied widely in the accuracy of their results. For instance, a widely publicized seroprevalence study ...
