The coronavirus test, which is offered daily to tens of thousands of residents in Los Angeles and other parts of California, could yield inaccurate results, according to a warning from federal officials that could raise questions about the accuracy of infection data that shape the pandemic response.
The Food and Drug Administration’s leadership warns healthcare providers and patients that the test conducted by Curative, a year-old Silicon Valley set-up that delivers the oral tests at LA’s 10 transit test sites, poses a risk. false results, especially false negative results. ”
To reduce the risk of false negatives, the Curative test should only be used on ‘symptomatic individuals within 14 days of the onset of the COVID-19 symptom’, and the swab should be observed and directed by a healthcare professional. the FDA said.
The guideline, issued Monday, repeats the instructions issued by the FDA when the test was first granted an emergency use authorization.
Los Angeles Mayor Eric Garcetti’s warning seems to be sharply contradictory, making coronavirus testing available to anyone in April, regardless of symptoms. In August, Garcetti said he disagreed with the leadership of the Centers for Disease Control and Prevention that the tests should only be given to symptomatic patients.
The conflicting approaches raise new questions about the accuracy of the city’s reported COVID-19 positivity rates, including whether false negatives gave the wrong assumption that they could ignore public health guidelines and engage with others outside their households, which contributes to the community spread.
Curative, founded by a 25-year-old British businessman, has taken more than 11 million tests nationwide, including in other major cities such as Chicago, San Francisco, Houston, Atlanta, Miami and Seattle. The company has a $ 42 million contract to conduct tests in U.S. military treatment facilities and also tests members of Congress, including those who have no symptoms.
Unlike nasal swab tests, which must be administered by a medical professional deep into a patient’s nose, the Curative test is a mouth swab that can be self-administered. Patients should cough three times, swing the saliva in their mouth and then rub a cotton swab around their gums, cheeks and tongue.
The Times reported in April that while the process of Curative is much more convenient than that of the nasal swab tests and that the tests are much more widely available, it is not the method recommended by the FDA, and may be less accurate. be.
Los Angeles County stopped curative testing at its test sites in June with Curative. The director of public health, Barbara Ferrer, said at the time that nose tests yielded fewer false negatives.
Dr Clemens Hong, who oversees coronavirus testing in LA County, said in an email that the country is aware of the FDA’s guidance and that it “assesses and evaluates the results of clinical trials.” He said that any type of oral swab test poses a risk of false negatives because the results depend on the correct collection of the saliva sample and the virus load it contains.
Curative still processes a “limited number” of tests on pop-up test sites supported by the country, Hong said.
The city continues to administer the Curative mouth-swab test at ten throughput and start-up test sites, including a massive facility at Dodger Stadium that processes thousands of tests a day.
When the province stopped using the Curative tests, Garcetti spokesman Alex Comisar said Los Angeles was “confident in the Curative test kits and lab work.”
Since the end of March, more than 3.37 million coronavirus tests have been administered at the city’s test sites since the pandemic began, according to city data. Many of these tests were processed by Curative.
A Curative representative said in a statement that the company’s test had been ‘validated and presented during the emergency pandemic, and was marked with specific warnings, precautions and restrictions that the FDA has repeated in the Safety Communications. However, the test performance and labeling did not change, and the company also did not observe any changes in the test performance. ”
The Curative study conducted to validate the test excludes patients who were asymptomatic, and the company said in its application for emergency approval to the FDA that the test was ‘limited to patients with symptoms of COVID-19’.
When the FDA issued an emergency authorization for the Curative test in April, it approved the test specifically for samples “from individuals suspected by their healthcare provider of COVID-19.”
The FDA’s guidelines warned that the Curative test “should be observed and directed directly during the sampling process by a trained health professional on the sample collection site.”
At Dodger Stadium, patients pass the test inside their cars. A video showing the correct method of applying the swab is played back on the massive screens at the test site, and the bag with the test stock – which is handed in through the car window – also contains instructions.
Curative is one of dozens of companies that quickly detected a coronavirus test and obtained emergency approval from the FDA after the agency announced in late February that it was removing regulatory barriers.
Undertakings with emergency consent may not promote their tests as ‘safe or effective’ for detecting the virus. The policy saves companies from complying with approval guidelines that can take up to two years.
Times authors Soumya Karlamangla and Melody Peterson contributed to this report.