If the blood tests are accurate and the research
well done, the studies could help scientists
determine what proportion of infected people
never had clear-cut symptoms. They also
could tell scientists exactly how deadly the
coronavirus really is, by finding the real number
of infections.
One day, the studies will help government
officials figure out how many people have
gained immunity to the virus. Such information
could guide decisions about when to lift stay-
at-home orders.
ARE THE TESTS ACCURATE?
Dr. Jeffrey Engel, executive director of a
national organization of disease investigators,
the Council of State and Territorial
Epidemiologists, said the first question he
would ask is what test was used.
Dozens of blood tests are being marketed
in the United States that are not entirely
accurate and are not comparable to each
other, according to a report released this week
by researchers at Johns Hopkins University.
Even a small rate of false positives can
substantially distort the understanding of
how many people have been infected. It’s
even possible false positives could outnumber
real positives.
The Food and Drug Administration is
overseeing a validation process for ensuring
that commercial tests are accurate. So far the
agency has authorized only four. Dozens of
other tests are being marketed in the U.S.
without such authorization.