One of the first states to receive rapid, low-cost coronovirus testing from the US government is warning against their use in asymptomatic people, a group that was expected to benefit the most from the technology.
Antigen test such as a Abbott Laboratories that seek telltale viral proteins may miss some infections that may have been picked up by expensive gold standard assays, and incorrectly produce positive results. Rapid tests are not recommended for people without exposure to a Kovid-19 patient, and those who undergo one should be informed of the limitations, the Louisiana Department of Health said The guidance was released last week.
The recommendations highlight issues with tests such as Abbott’s $ 5 binaxo that the US Department of Health and Human Services is spending Over $ 750 million and used in White house State health officials are raising concerns that people with no symptoms should be screened with a more expensive but more reliable polymerase chain reaction because of concerns about rapid test performance, according to Jeff Engel, senior consultant. State and Territorial Epidemiology Council.
HHS “made the purchase on novel uses without any studies in which they are deploying these tests,” Engel said. “I think it’s careless.”
HHS said in an email the agency’s spokesperson, Mia Heck, is providing antigen testing for use in symptomatic and asymptomatic people. Broadly, inexpensive rapid antigen testing helps slow the spread of the virus, and when used as an objective, tests such as BinaxNOW can detect the possibility of being contagious, Abbott said in an email . Its shares gained 3.6% in New York at 12:51 pm.
The US Food and Drug Administration also issued an alert on antigen tests, Warned on Tuesday that they could produce false positive results. An FDA statement said populations with low virus prevalence are likely to have problems or when the test is performed improperly.
The FDA stated that nursing homes and other care settings reported false positives from antigen tests. Any type of examination is subject to some inaccuracies, and it is important to follow the instructions of the antigen test, confirm the results when needed and consider the possibility of a false positive when looking at the results.
Antigen tests detect unique protein markers on the surface of SARS-CoV-2. They do not require heavy-duty laboratory equipment and can produce results at a fraction of the cost of 15 minutes and PCR tests.
This would make them ideal for places like schools – but in general young people are less likely to have Kovid symptoms. Although federal authorities have pushed for widespread use of the tests, they were only approved by US regulators for use in symptomatic people, based on research in that population, state officials note.
Louisiana, plunged by back-to-back hurricanes, was the initial recipient of antigen tests from the US, receiving around 305,000. The lack of clarity about testing capabilities has left the state in a gray area, said Joseph Canter, interim assistant secretary for the state’s public health office.
“On the one hand, we have such technology and testing platforms that are new and potentially valuable. And everyone is interested in reaching them to those who can benefit from it as soon as possible. “On the other hand, we don’t have great data on them yet.”
The Oregon Health Authority recommends the use of BinaxWow, which shows asymptomatic people without citing accuracy concerns without risk factors such as Kovid-19 exposure. However, the authority does not recommend verifying positive antigen test results with PCR, stating that both are mistakes.
Other manufacturers of antigen tests include Quid Corp and Becton Dickinson & Co. is concerned about the accuracy of the antigen test before the U.S. sent thousands of tests to nursing homes nationwide.
Nevada told nursing home To stop using antigen tests last month, based on questions about their accuracy. The state later changed its stand. Louisiana previously also released interim in October Recommendations for nursing homes stating that residents without symptoms should be screened with PCR tests.
Read more: Rapid Kovid Test Push Weavers on Nursing Home False Positives
Linguistic questions are complicating US government pressure to distribute antigen tests more widely. Most states are implementing policies similar to Louisiana’s that recommend PCR testing for screening of heterosexual people, Engel said.
As tests are performed at locations that do not typically perform them, users can make mistakes, he said. He said that states can change their approach when more data is available.
Louisiana, according to Canter, is conducting shipping tests at colleges, school-based health centers, primary care clinics, urgent care centers and the Department of Corrections, among other locations. The state expects to receive a total of 1.4 million tests.
The health department’s guidance does not completely rule out using antigen tests in asymptomatic people. PCR assays should be used to confirm antigen results in certain conditions, such as when symptoms such as Kovid test negative or a person without symptoms or known Kovid-19 contact test positive, health officials said.
Louisiana has included use of Abbott antigen tests in response to screen personnel Hurricane Laura, Canter said. Overall, the performance of the tests was in line with expectations, and none of them planned formal studies, he said.
Brett Giroir, an HHS officer who leads the administration’s Kovid-19 clinical trial efforts, has voiced concerns about false results from antigen tests.
With the antigen test, he said, “We support the asymptomatic test used,” he said in a media briefing on 26 October. “That’s the only way you’re going to screen millions of people a month.”
Using antigen tests for One close Screening increases the likelihood of missing infections, especially early ones, said Mark McKellen, director of the Duke-Universities Center for Health Policy at Duke-University, who is working with Rockefeller Foundation to develop the Kovid-19 test protocol.
Screening individuals with regular antigen tests, as a partnership between Rockefeller and HHS, are at pilot sites across the country, including New Orleans, that can cut risks and allow for quicker identification of cases McClellan, formerly a former FDA commissioner, said the administration of President George W. Bush. The project will deploy 120,000 Abbott antigen tests and collect data about their performance and how good it is to use them in schools.
Ultimately, however, testing should still take place along with other measures such as masking and social disturbances.
“We are no longer in that position to go back to the normal way for people with one-time use of Kovid antigen tests,” said McClellan. “This is another layer of protection as we try to reopen and get through the epidemic.”
(Updates with manufacturers of antigen tests and Oregon guidance in the nursing home section.)