America Needs Rapid Covid Testing to Get Something Like Its Life Back

The next day, all 311 Likins residents took Covid tests.

Today, processing bottlenecks still render many test results worthless by the time people get them.

Over time, though, the problem of testing has attracted new focus, new thinking, and new money.

needs to test a lot more people a lot faster.

Faster, cheaper testing may not flag every new case of Covid, but that shouldn’t mean settling for the current level of blindness, with its torturous drip of preventable deaths.

And the technology to create tests for new viral diseases is so straightforward that it can generally be done in a few days.

11, the CDC did indeed create its own test in a matter of days—but because of regulatory requirements and limited access to the relevant viral samples, the agency’s Atlanta headquarters was the only place it could be done.

The tests in use at the time were molecular diagnostics known as polymerase chain reaction tests.

The process starts with enzymes being added to the sample, which is then repeatedly heated and cooled to create billions of copies of the viral genome.

But the hospitals, doctors’ offices, and pop-up testing facilities where PCR tests are given often don’t have the equipment to process the results on-site—the thermocycler that incubates the samples costs at least $100,000—so the swabs are usually sent out.

One, a lateral-flow test, is a disposable strip of cellulose or woven fiber—picture a home pregnancy test.

has long sold lateral-flow tests for hepatitis C and HIV.

In 2017 it created the only FDA-approved Ebola antigen test.

struggling to create reliable tests and its most advanced labs overwhelmed, Chief Executive Officer Stephen Tang saw the parallels.

What we have learned from experience is that people will test themselves more frequently in the privacy of their own homes.” Tang plans to build on the company’s HIV test platform to bring an at-home Covid test to market before the end of the year.

regulators to authorize a coronavirus strip test made to be processed in a lab.

Established testing companies are already bringing lateral-flow tests to market.

26, Abbott Laboratories announced that the FDA had awarded it an emergency use authorization for BinaxNOW, a 15-minute disposable antigen test priced at $5.

A so-called point-of-care test, it must be given by a health professional.

But since it requires no lab equipment, an unlimited number can be conducted and processed at any given time.

If we don’t have tens of millions of tests a day—and we don’t—who do we want to leave out?”.

A test with low sensitivity will miss lots of cases; a test with low specificity will mistakenly tell people they have a disease when they don’t.

Lateral-flow tests are neither as sensitive nor as specific as PCR tests.

There are concerns that tests done at home, where people swab their own noses instead of having a professional do it (or at least supervise), could further lessen the sensitivity.

Mammoth Biosciences Inc., working with a microbiologist named Charles Chiu at the University of California at San Francisco, is using the DNA-splicing technology Crispr to improve the accuracy of strip tests.

The other, in development with GlaxoSmithKline Plc, manages to replicate this approach, with the attendant sensitivity, in a self-contained and disposable kit not unlike a lateral-flow test.

Another school of thought, though, holds that worries about the sensitivity of strip tests miss the point.

Mina argues that we should essentially test everyone all the time, everywhere.

Tests at the entrance to offices and schools would visibly ensure the safety of those spaces, encouraging people to return to them.

People who test positive could immediately isolate themselves, breaking the chain of transmission.

In this world, a strip test’s relative insensitivity would be less of an issue—positives could be double-checked to make sure they’re correct, and false negatives would be caught a day or two later by the next test, still early in the disease course.

In that sense, he argues, strip tests can better gauge an individual’s risks to the broader population.

These are actually the intervention, like a vaccine, to suppress population spread.” According to his modeling, testing just half the population every three days would bring Covid under control within weeks.

To make this a reality, the FDA would need to relax its testing standards down from PCR-level sensitivity, and someone would need to manufacture and pay for the untold billions of tests.

The first point in Joe Biden’s seven-point Covid plan is to “ensure all Americans have access to regular, reliable, and free testing.” The plan mentions at-home and instant tests and proposes a testing board modeled on Franklin D.

President Trump has publicly called for less testing, and his CDC recently said asymptomatic people who’ve had contact with a sick person don’t need to be tested.

And the agency is already distributing a different type of antigen test to nursing homes across the country.

(New York City’s school system has more than 1 million students.) The production of billions of new tests could create supply chain problems of its own, and the millions of false positives and negatives that would be produced at that scale could further undermine Americans’ shaky confidence in their public-health system, a dangerous prospect in a country where large numbers already refuse to wear masks.

There’s also no mechanism to compel people who test positive at home to stay there, especially if they’re living paycheck to paycheck without paid sick leave.

Whether or not Mina can sell the idea of regular tests for all, the importance of faster, more widespread surveillance testing has become clear.

Such a model could use strip tests, if they can be scaled up, or it could rely on methods such as pooling—combining multiple samples to increase the throughput of labs.

Nursing homes and hospitals are places where people should be tested all the time, he argues, with meatpacking plants, prisons, and schools close behind.

If we don’t have tens of millions of tests a day—and we don’t—who do we want to leave out?”.

In August, a group of governors announced a joint effort with the Rockefeller Foundation to purchase millions of antigen tests

“Had we had ongoing funding to do diagnostics for Zika, maybe the tests that we’re now struggling to develop in real time would have already been developed.”