The Mudcat Café TM
Thread #167504   Message #4072225
Posted By: Stilly River Sage
17-Sep-20 - 12:21 PM
Thread Name: BS: New news on the pandemic COVID-19
Subject: RE: BS: New news on the pandemic COVID-19
That paper has a paywall that pops up pretty quickly. Here are snippets of it.

The Food and Drug Administration recently issued emergency use authorization for the BinaxNOW COVID-19 Ag Card rapid test, produced by Abbott, a medical device and health care company.

The company plans to begin shipping tens of millions of rapid tests this month, increasing to 50 million per month by October. That means the U.S. could have the capacity to test more than 1.5 million Americans a day in October.

In the past week, there have been between 588,965 and 911,329 daily tests performed in the U.S., according to Johns Hopkins University. In Texas, the number of daily tests administered over the past week has ranged from about 58,000 to 98,000, according to Johns Hopkins. . . .

Test accuracy
Molecular tests like the PCR, or polymerase chain reaction, test has been the most common test throughout the pandemic. It is taken as a nasal swab, or it can be taken as a throat swab or saliva sample. Those samples are taken to a lab for processing and can take days to produce results.

Antigen rapid tests work differently by looking for a virus’s proteins. Antigen tests deliver results in a few minutes and are administered with a swab from the nose or throat without the need for the sample to be taken to an offsite lab. Because the results come back so quickly, there has been some doubt regarding their accuracy.

Within the first week of symptom onset, Abbott’s new test has a 97.1% positive percent agreement, meaning it is accurate by that percentage when a patient is positive, and a 98.5% negative percent agreement, meaning it is accurate by that percentage when a patient is negative, according to Abbott.

“In order for them to be a practical option, they have to be inexpensive, involve an easy sampling method, be readable in under an hour ideally, and be at least 70 to 80% accurate,” Petrosino said.

Even if Abbott’s test or other rapid tests were less than 70% accurate, they would still be “tolerable,” according to Petrosino because a follow-up test could be administered to double check.

“Highly accurate tests are ideal, but we know that the tests with the greatest accuracy are molecular tests,” Petrosino said. Because molecular tests require a deeper nasal sampling and need to be processed in a lab, they’re more expensive and require more time, according to Petrosino.

“And [it] involves a sampling method that is uncomfortable,” Petrosino said.

More tests to come
Abbott’s rapid test isn’t the only one that has received emergency use authorization by the FDA. In August, Yale School of Public Health was granted authorization for its SalivaDirect COVID-19 diagnostic test. While most COVID-19 tests require a nasal swab, Yale’s test uses a spit sample — one of five saliva sample tests that have received approval by the FDA.

Such a sample can be collected in any sterile container compared with nasal COVID-19 tests, which require extraction kits that are sent to off-site laboratories.

“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,” Dr. Stephen M. Hahn, FDA commissioner, said in a statement.

Sometimes if you open an article from Twitter it lets you see content.

Dallas Morning News article