Beat Covid Without a Vaccine

Home testing and ‘digital passports’ could stop outbreaks

By Laurence Kotlikoff and Michael Mina. Mr. Kotlikoff is a professor of economics at Boston University. Dr. Mina is an assistant professor of epidemiology at the Harvard T.H. Chan School of Public Health. Excerpts:

"The Centers for Disease Control and Prevention says it’ll be mid-2021 before a Covid-19 vaccine is available in quantities sufficient to “get back to our regular life.” Does that mean nine more months of lockdown? Not necessarily. There’s an alternative: repeated, frequent, rapid at-home testing. At least one such test, Abbott Labs ’ BinaxNOW, is already being produced for the government. Others are in development.

Details vary, but each is simple enough to be self-administered. With the BinaxNow test, you swab the front of your nose, insert the swab into one side of a small card, add saline to the other side, close the card, and see if the reader on the front lights up green or red. A phone app records a negative result for use as a digital passport.

Asking those presumed to be infectious to stay home would cut transmission chains, ending Covid outbreaks within weeks. Each transmission stopped may prevent hundreds more. This isn’t herd immunity, but it has the same effect. Like vaccines, the tests don’t have to be perfect. It’s enough to drop the virus’s reproductive number (the average number of people each infected person infects) below 1.

Cornell University’s quick defeat of its Covid cluster shows the power of frequent testing. Cornell tests all undergraduates twice a week and quarantines those who are positive. After an unauthorized party, Cornell had 60 positive cases a week before starting surveillance testing. It now has about three a week."

"Current rapid tests, including Abbott’s, generate 2% false positives, too high for at-home use. Each pack of tests must come with a confirmatory test that detects a different part of the virus. Both would need to turn red to deem a person positive. This plus repeat use 24 hours later could drive the false-positive rate well below 0.1%."