Eleven of 14 antibody tests available on the market for the Coronavirus Disease 2019 (COVID-19) have an accuracy of 95 percent up, but doctors say these still need to be tweaked to "restart the world's economy," according to the Daily Mail.

The tests were split into two separate studies by a team of 50 researchers under the COVID Testing Project. They were partly funded by the Chan Zuckerburg Biohub, the charity of Facebook CEO Mark Zuckerburg and his wife Priscilla Chan.

The researchers sampled the blood of 80 participants who have COVID-19. 108 blood samples donated before the pandemic and 52 blood samples from people with other viral infections but tested negative for COVID-19 were also taken.

Remarkable results

Chan Zuckerburg Biohub and Massachusetts General Hospital found that only three tests had an accuracy rate of over 99 percent. These were made by Sure Biotech, Wondfo Biotech, and the researchers' in-house. Eight other tests scored 95 percent.

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Sure Biotech had a 100 percent specificity. This means the test was able to generate a negative result correctly for people without COVID-19. Specificity is also known as the "true negative" rate. 

The COVID Testing Project studied 12 tests with a specificity of 84 percent, while Massachusetts General Hospital has yet to release the data for the two tests it studied. "The New York Times included it in a survey of all 14 this weekend," according to the Daily Mail.

According to HealthNewsReview, "A high-specificity test will correctly rule out almost everyone who doesn't have the disease and won't generate many false-positive results."

The researchers also studied tests from Bioperfctus, BioMedics, DecomBio, DeepBlue, Epitope ELISA, Innovita, Premier, UCP Bioscience, and VivaDiag.

Numerous tests are being sold to the United States by manufacturers - some of them antibody tests that will hopefully reveal immunity to COVID-19.

Escalating Doubts

However, the tests are raising questions and doubts because they are not yet FDA-approved. The research is not peer reviewed yet. 

As of April 28, the pandemic has over 3.04 million confirmed cases, 895,000 recoveries, and 211,000 deaths.

According to the Daily Mail, "Many [tests] return false positive results and it remains unconfirmed that even when antibodies are accurately detected, that they offer long-term immunity to the virus." 

Dr. Alexander Marson, one of the leading scientists on the 14-test project, said, "There are multiple tests that look reasonable and promising. That's some reason for optimism." 

But some doctors like infectious diseases expert Dr. Michael Osterholm from the University of Minnesota said, "It seems like all of a sudden, everybody just decided that antibody tests are going to give them some grand answer." 

It's also dangerous to rely on them, according to epidemiologist Saskia Poepscu from George Mason University to the New York Times.

But the results of the study, researchers said, can be useful against COVID-19. The Daily Mail said, "so long as the data is being read properly by well-trained scientists, it can work as a tool to beating the pandemic." 

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