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Island COVID-19 Task Force member Dr. Hanley provides details on testing

By PAULETTE LeBLANC - | Nov 18, 2020


According to Dr. Daniel Hanley, who is a member of the Pine Island COVID-19 Task Force, there are two main types of testing for the coronavirus.

“One involves directly finding specific parts of the virus, and the other detects the consequences of infection,” said Hanley. “The first part is known as molecular testing and identifies individual parts of the virus that make up its genetic code, called nucleic acids. The second checks for the antibodies that your body makes to help you fight the infection.”

The island doctor said initially the tests were based on amplifying the specific nucleic acid sequences via a method called PCR to see if you have an active virus building up in your body. He said this is done regardless of any symptoms.

“Testing each sample can take hours, and when thousands of samples are coming in hourly, the backload builds up quickly, which is why results are often delayed,” Hanley said. “This is where the drive-through testing has been focused. These tests currently remain the standard.

“Antigen detection are newer types of tests designed to check for active infection via the proteins generated by the virus,” he continued. “However, they are still limited in their availability and lack sensitivity.”

He said, for example, a negative test may not necessarily mean you do not have the virus. Another type of testing is antibody testing, which involves blood draws.

“Usually, once your body gets an infection, your immune system figures out how to fight it, which does take time,” Hanley said. “The various antibodies generated help fight future infections. We can detect them and can see if you had a previous infection — the main issue with coronaviruses in general, which usually causes a cold, is that the antibodies your body makes don’t last very long — perhaps a few months.

“Ending the pandemic requires accurately applying these diagnostic tests in high volumes. Ideally, these results would help us guide therapy and prevent further spreading. Regulatory obstacles exist to help clarify how well they work before widespread use, but EUAs (emergency use authorizations) lower these barriers and are designed for speed in situations such as this pandemic. This means that while the accuracy of these tests has not always been up to par, the technology continues to improve.

“I would expect testing for coronavirus-19 to become part of the standard panel of testing for upper respiratory illnesses, such as RSV, flu A/B, and depending on the specific situation, strep throat. In the meantime, we are not there yet, and ending the pandemic continues to be a collaborative effort,” said Hanley.