Why don’t Americans get flu tests at home?

debtle season in progress.rsv puts number of records children in hospital.And medical professionals are preparing Another Covid winter.

With so many potential viruses involved, it would be helpful if Americans had a way to distinguish between different illnesses at home. home test It helps telemedicine doctors determine when it makes sense to prescribe treatments like Paxlovid and Tamiflu. These treatments should be administered within a specific time frame after the onset of symptoms.

“A home test for flu helps ensure that people who need and receive flu antivirals are the ones who need them most,” said Christina Yen, an infectious disease physician at the University of Texas Southwestern Medical Center. I will.” We make treatment decisions based on data. ”

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However, it is not possible to purchase a flu test at home in the United States. This is not due to lack of technology. A rapid antigen flu test in a doctor’s office is “virtually identical” to her Covid test, which is already being done in people’s homes, said her associate Zoë McLaren. She is a professor of public policy at the University of Maryland, Baltimore County, studying health policy for epidemics.

Rather, the problems come down to past hang-ups, and digital fixes need to be found to address them.

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Michael Mina, a former assistant professor of epidemiology at Harvard University, said, “It’s very rare and very new that people are allowed to know what’s going on in their bodies without the intervention of a doctor. That’s it.

T.The Food and Drug Administration has historically delayed approval of over-the-counter tests, Mina said, citing pregnancy tests as an example. 26-year-old female product designer prototyped a home version of the lab pregnancy test in 1967, but no home pregnancy test was approved in the United States until 1977. Did she get pregnant on her own without a doctor in the room? Women have been doing it for millions of years, so it’s a silly concern,” Mina said.

The FDA has been equally cautious about home testing for HIV. approval year 2012.

2016 FDA advisory boardOpinions were divided on whether the benefits of over-the-counter flu tests outweighed the risks. Experts debated whether home testing would actually be effective in keeping people at home if they knew they or their children had the flu, according to the conference minutes, with one panelist joked that daycare centers might make decisions for parents if over-the-counter.

“Women will want to go to work and they will want to leave their children in daycare,” one panelist said. [could say] Say, “If your child has symptoms, we’ll test you,” and if it’s positive, send the child home.

The room laughed at the thought.

This scenario is not laughable in the wake of the pandemic.At the peak of the Omicron waves, almost Quarter Symptomatic people were testing themselves at home. Many Americans have apparently grown accustomed to the idea of ​​testing at home and the fact that they may have to adjust their plans if they get a positive result.

But regulators and clinicians remain concerned. Home testing may be less accurate than testing performed by a health care practitioner because sufficient samples may not be available to obtain a valid result or the results may be difficult to read correctly. Also, while HomeHer users typically take positive or negative results at face value, clinicians have more context to interpret false positives or false negatives. They may order more sensitive tests, act more cautiously on those they know are at risk, or decide to treat patients anyway because of suspected false negatives. You may.

There are also historical concerns about the low accuracy of rapid influenza tests and varying sensitivities from year to year. Prior to 2009, measuring viruses by cell culture had been the standard for decades, but the number of cell cultures could vary greatly depending on whether the laboratory had good or bad cell cultures.

During the 2009 H1N1 pandemic, more consistent nucleic acid amplification tests such as PCR became the new normal. When compared to the PCR method, rapid antigen influenza testing appeared to be significantly less reliable than when cell culture-based tests were first approved.

Based on protests from the medical community against rapid flu tests 11% of samplesIn 2017, the FDA reclassified antigenic influenza tests from Class I devices to Class II, which is considered a higher risk. FDA started demand Manufacturers must certify testing against eight influenza strains. These strains change from year to year depending on the prevalent variant. These year-to-year variations can be a concern if people store flu tests in their medicine cabinet and pull them out months or years later.

T.Here may be a way to address concerns about patients performing and interpreting home testing incorrectly. During ~Mina currently serves as Chief Scientific Officer.

However, while the eMed test is marketed as an at-home flu and Covid test, the kit only includes the FlowFlex rapid Covid test. Clinicians cannot ask patients to be tested for the flu as they would if they were in person because there are no approved home flu tests. Follow the guidance in For example, if a patient is Covid-negative during flu season, they probably have the flu, and clinicians may decide to prescribe Tamiflu. As noted, this setting may lead telemedicine clinicians to over-prescribe antiviral medications.

The situation is particularly frustrating because of the CLIA-waived rapid flu tests. This means it is approved for use at point-of-care testing sites such as pharmacies and clinics, not at home.

“as if [the FDA] We live in a world where the internet and telemedicine don’t exist yet,” Mina said. “There are ways to get tested at home without having to take responsibility for interpreting the results yourself.” We envision a scenario where the FDA could expand access to diagnostic testing by setting up CLIA-exempt appointments.

It’s unclear if the FDA would support that kind of change, but a senior FDA official said the agency is now trying to find better ways to bridge point-of-care and home-based approvals.

The official also said the administration was “strongly supportive” of home testing for respiratory viruses, even before the pandemic. However, the companies developing these tests have a different impression from their interactions with the FDA. “I’m glad they said that,” said Wade Stevenson, senior vice president of marketing for the rapid PCR test maker. Visby Medical.

Stevenson acknowledged that the FDA has a tough job. The FDA is trying to protect the products available to the American healthcare system without stifling innovation. “When you submit a new idea to the FDA, they usually get excited about it,” Stevenson said. “They like to see new ideas. They encourage development and want people to push boundaries. ”

However, manufacturers are frustrated by claims that the path to OTC testing approval is unclear and the goalposts are constantly changing.

One of the obstacles faced by manufacturers like Bisbee is the question of what the FDA wants in home testing. The FDA strongly encourages trial manufacturers to be involved by submitting presubmissions for feedback. But Stevenson said the FDA’s presubmission guidance came too late to help develop clinical trials. Influenza, especially the low-incidence influenza B epidemic, has been so volatile in recent years that clinical trials take a long time to complete.

Stevenson believes Visby’s at-home PCR test is “a long way off.” One reason, he said, is that the latest proposal the company has received from his FDA specifies that the administration wants to incorporate public health reporting into home testing.This will help address issues facing Covid testing today that are not included in reported case numbers. Unreported home testingHowever, including this feature is “not trivial” because each state has its own reporting standards and how it collects that data.

“The FDA saying, ‘Think about this,’ is great and well-intentioned,” Stevenson said. I don’t know how to do that. ”

B.Even after a test is approved, it will be difficult for test manufacturers to move into the home market. This is because at-home testing is typically not covered by insurance, but laboratory diagnosis is typically covered. In 2020, Congress required insurance companies to cover Covid tests for free, but the provision continue only During a national public health emergency. Home testing is ostensibly intended to lower barriers to access to healthcare, but CDC investigative show People most likely to use at-home COVID-19 testing are highly educated, high-income, and white. This means that if at-home flu tests are approved, a lot more work will have to be done to ensure that they actually reach everyone. population.

Currently the only test available to distinguish between flu, Covid and RSV at home is Labcorp pixel Users swab themselves at home and send samples for lab testing. However, this test takes 1-2 days for him and cannot compete with at-home tests that give results in 15-30 minutes.

Some Covid test makers are now turning to include influenza in their samples. cue health When Lucilla’s health have both submitted Emergency Use Authorization for Covid and Flu Home Testing. Both are molecular-based amplification tests, so they may avoid some of the concerns about antigen test sensitivity. The companies also offer a companion app to help connect patients to treatment options such as Paxlovid and, if approved for influenza, Tamiflu. However, neither has yet been approved by the FDA.Lucilla’s test licensed in Canada When Europewas submitted for approval in May, while Cue Health’s request was submitted at the end of September.

“We are in constant communication with the FDA,” said Debkishore Mitra, founder and CTO of Lucira. “I really hope that we can have some impact on the current flu season.”