By Steve Gorman
LOS ANGELES (Reuters) - The mayor of the second-largest U.S. city has joined a growing clamor among health experts and politicians for a radical shift in the nation's coronavirus testing strategy - from an emphasis on the utmost accuracy to a focus on speed and simplicity.
The concept envisions mass production and distribution of low-cost, do-it-yourself diagnostic kits based on paper-strip designs that can be used frequently and produce results in minutes, similar to home pregnancy tests. No lab equipment or special instruments would be required.
Los Angeles Mayor Eric Garcetti said this week he has convened a team of public health experts, bioscience executives, government leaders and philanthropists to push for accelerated research, development and production of such tests.
Proponents say that rapid, at-home COVID-19 testing would allow for real-time detection of new clusters of cases, including asymptomatic individuals - before they can spread. Such a feat has proven unattainable within the existing testing framework, which relies on laboratories to process samples and typically takes days or weeks to return results.
"If we get this right, we could be doing as many as a million tests a week using paper strip testing just here in Los Angeles," Garcetti said on Wednesday, as the city appeared to be on the verge of tamping down its latest surge of infections.
When paired with expanded contact-tracing to locate and quarantine other exposed individuals, rapid in-home test kits could be as effective as a vaccine in breaking the COVID-19 transmission cycle, according to advocates led by Harvard University epidemiologist Michael Mina.
'AT WARP SPEED'
"They can effectively be akin to a vaccine that was introduced tomorrow," Mina told a recent conference call with reporters, as quoted by the Harvard Gazette. The tests could be produced for as little as $1 a piece, he said. "This is something we can actually do at warp speed."
Mina, Garcetti and other proponents have said such a breakthrough is critical as state and local leaders struggle to find ways to reopen schools, universities and workplaces safely.
To date the respiratory virus has claimed some 5,200 lives in Los Angeles County, one of the nation's COVID-19 hotspots, accounting for nearly half of California's deaths from the pandemic.
Mina said he envisions making home diagnostic kits so widely available Americans could test themselves daily, or every other day, as a matter of routine.
The new test kits would be based on antigen detection technology that scans saliva or nasal mucous for the presence of viral proteins.
This method, while quick and simple, is generally far less sensitive - with more frequent false-negative results - than the current gold standard of COVID-19 screening, called polymerase chain reaction, or PCR, tests, which look for traces of viral genetic material.
QUICK OR PRECISE
That difference, according to Mina, has led to one of the chief roadblocks to biotech companies developing at-home antigen tests - reluctance by the Food and Drug Administration (FDA), which recommends over-the-counter, non-lab tests perform at a minimum of 90% sensitivity. FDA recommends at least an 80% rate for prescription at-home tests to be used under a doctor's supervision.
"Until the regulatory landscape changes, those companies have no reason to bring a product to market," Mina said.
Mina and others, including Dr. Ashish K. Jha, a Harvard professor of medicine, insist that from a public health perspective the accuracy of home antigen tests are sufficient.
In a commentary published by Time magazine, Jha cited government data suggesting that the current testing regime is only detecting one in 10 Americans who are infected.
Responding to a Reuters query, the FDA said in a statement that it would consider alternatives, including a "strategy that involves serial testing using less sensitive tests to achieve performance."
But FDA support for such a strategy would hinge on available information showing that benefits outweigh risks and addressing "the capacity to manufacture a sufficient supply of tests with which to conduct multiple tests per person," the agency said.
(Reporting and writing by Steve Gorman in Los Angeles; Additional reporting by Carl O'Donnell in New York and Allison Martell in Toronto; Editing by Bill Tarrant and Daniel Wallis)