The Food and Drug Administration on Saturday authorized emergency use of a new and inexpensive saliva test for Covid-19 that could greatly expand testing capacity.

The new test, which is called SalivaDirect and was developed by researchers at the Yale School of Public Health, allows saliva samples to be collected in any sterile container. It is a much less invasive process than the nasal swabs currently used to test for the virus that causes Covid-19, but one that has so far yielded highly sensitive and similar results. The test, which also avoids a key step that has caused shortages of chemical reagents used in other tests, can run approximately 90 samples in fewer than three hours in a lab, although the number can be greater in big labs with automation.

Moreover, Yale intends to provide its “open source” testing protocol to laboratories around the country. Other labs can now adopt the method while using a variety of commercially available testing components that can reduce costs, speed turnaround times and increase testing frequency, according to the FDA. And because the reagents for the test cost less than $5, the Yale researchers estimated labs should charge about $10 per sample, although that remains to be seen. The testing method is available immediately, but the researchers added it can be scaled up quickly for use in the coming weeks.

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“Providing this type of flexibility for processing saliva samples to test for Covid-19 infection is groundbreaking in terms of efficiency and avoiding shortages of crucial test components like reagents,” said FDA Commissioner Stephen Hahn in a statement. The agency has previously authorized four other tests that use saliva for sampling, but these yielded varying results.

The authorization occurs amid ongoing disarray over Covid-19 testing. The U.S. has been plagued by an inconsistent strategy for detecting the virus, thanks in part to persistent shortages and the use of a variety of different tests that have sometimes yielded unreliable results.

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The inability to quickly and efficiently test Americans has, in turn, made it much harder for government officials and the medical community to accurately assess and predict the path of the virus. For this reason, the FDA move was greeted with enthusiasm by some public health experts, who have bemoaned the ongoing spread of Covid-19.

“This could be one the first major game changers in fighting the pandemic,” tweeted Andy Slavitt, a former acting administrator of the Centers for Medicare and Medicaid Services in the Obama administration, who expects testing capacity to be expanded significantly. “Rarely am I this enthusiastic… They are turning testing from a bespoke suit to a low-cost commodity.”

Yale’s saliva-based test also skirts a step that other Covid-19 tests require: extracting the virus’s genetic material. Extraction kits are one of many components of the existing diagnostic tests that have faced shortages. Supply issues have limited testing capacity overall, as well as slowed how quickly results can be returned.

“Widespread testing is critical for our control efforts,” Yale researcher Nathan Grubaugh said in a statement. Grubaugh added: “If cheap alternatives like SalivaDirect can be implemented across the country, we may finally get a handle on this pandemic, even before a vaccine.”

The research team validated SalivaDirect in part by testing NBA players, coaches, and staff, and Yale said the test is now being studied in asymptomatic people through the program with the NBA and its players union.

  • The fact that they admit skipping the extraction step is the biggest downfall to these rapid tests. High complexity PCR requires purified DNA/RNA to reduce inhibitors and lowers the Limit of Detection which provides greater accuracy. Also, there needs to be a collection process that has the efficiency to pick up the most concentrated viral particles. This is way nasopharyngeal is the best method for collection because COVID-19 is a respiratory virus and congregates most far into the nasal cavity. Saliva has a very low viral load and may not pick up enough virus for it to be detected if the person is asymptomatic.

  • Massive Testing, at this point accomplishes absolutely nothing of value except to keep the economy on lockdown.The vast majority of cases are asymptomatic. The whole point of testing was to quickly identify and quarantine those that have it! But we r not doing that, are we ?? Instead we are still quarantining the entire country. Just because there has been an artificial rise in cases courtesy of the cdc method of counting. Ridiculous, I subscribed to this in order to get the latest accurate info about covid. Instead u get nothing but propaganda about testing and vaccines. The whole world is laughing at the U.S. and Europe as other countries, 3rd world countries recover thru the use of cheap hcq. While we let faucci and gates dictate our every move.

  • The other factor that has made it difficult to predict and control breakouts is the CDCs insistence on counting every positive test as a reliable indicator that 12 other people have it as well. No wonder the cases are skyrocketing. But the deaths are not. U can go ahead and put covid down as the cause of death for everybody that dies and u still cant keep up with the fake # of cases

  • Being cautious around testing is wise but don’t be so quick to dismiss this new saliva test due to other research going on. The FDA approved it so there must be at least a 90% accuracy rate (note that antibody tests have not been approved because they fall below this percentage). Testing will never be 100% accurate but the more options we can offer, the better. That and for the public to embrace and practice social distancing, wearing of masks and washing hads frequently.

    • This is the problem with public education on the subject. The FDA lowered the accuracy rate to 80%, first off. In reality, when presented to the general public, the accuracy rate is more around 60-70%. This is because validations are conduced in a controlled way though two avenues; 1) by using patient samples of known positives and negatives. The problem with this is that the positive sampes are collected from people who are expressing severe symptoms for a virus where 90% of the population is asymptomatic. Usually there is a substandard range of viral load collected and quantitated to establish true sensitivity. 2) through synthetic samples which can be manipulated to be more robust than a true sample through gene manipulation. On paper it looks fine, but when put into practice it falls short of expectations and produces a false sense of security through false negatives which defeats the propose of trying to control the virual spread.

  • I have little faith in rapidly developed quickly released tests. We have seen far too many false positives and negatives, sometimes in tests given hours apart. Most people are not retested that quickly, so the false results we are aware of are likely just the tip of a very large iceberg. I am not a medical professional, but it seems to me that far too much weight is being given to mass testing when it reality items like masks and social distancing are valid tools that require very little second guessing. It is the behavior of people who chose to ignore common sense guidelines that are fueling this virus, not a lack of testing…..

    • Wrong-so wrong. Testing is the only way to know for sure you have it. Wearing a mask only protects others, not yourself. Many don’t care about anyone but themselves. You can’t make others behave properly, so living in a world that says you have to wear a mask and social distance, is a dream world. This isn’t China were we can force people to do these things. Testing is what we need.

    • Even the HIV test still gives false positives and two or three different tests must be used for a diagnosis or clearance.

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