(Reuters) – COVID-19 screening tests used at airports, schools, and other public places are not particularly effective, a large analysis shows.
Researchers synthesized the evidence from 22 studies of various screening methods, including taking people’s temperature, asking about symptoms, travel history and exposure to infected or possibly infected people, and combinations of those and other approaches.
All of these, as well as repeated screening, had low “sensitivity,” meaning poor ability to identify those with COVID-19, and low “specificity,” that is, they could not reliably identify those without COVID-19. The specificity measure tended to be more accurate in places with low infection rates.
With these popular screening methods, “a high proportion of infected individuals may be missed and go on to infect others, and some healthy individuals may be falsely identified as positive, requiring confirmatory testing and potentially leading to the unnecessary isolation of these individuals,” the researchers wrote last Tuesday in a review for The Cochrane Library.
“Given the poor sensitivity of existing approaches, our findings point to the need for greater emphasis on other ways that may prevent transmission such as face coverings, physical distancing, quarantine, and adequate personal protective equipment for frontline workers.”
