HARLINGEN, Texas – As testing ramps up in the Rio Grande Valley, people need to know which COVID-19 test is most accurate.
Dr. James Castillo, Cameron County Health Authority says there are currently three COVID-19 tests being used in the Rio Grande Valley, and they vary in accuracy and time to get results.
Dr. Castillo says the PCR or swab test is the best and most accurate. The test is commonly used for confirmation of the virus, however test results can take days even up to a week to receive results.
Castillo says the newest form of testing is the antigen test, which looks for the coding of the virus. While the test is accurate when positive, and yields fast results sometimes in under an hour, Dr. Castillo says the test can miss detecting the virus.
The third is the antibody test, which tests your blood. Dr. Castillo calls the test unreliable and adds the FDA does not recommend the test to diagnose acute COVID-19. In other words if you have symptoms that test is not recommended.
Dr. Castillo adds that particular test is useful to see who had COVID-19 in the past and have now recovered, so that their plasma can be used to treat other patients fighting off the virus.
Dr. Castillo says whatever test you take, while results are pending you should quarantine.
“You need to act like it’s positive. If you think you need to get tested because you’ve been exposed you need to quarantine. If you think you need to get tested, because you have symptoms you need to act like that test is going to be positive. That way we can use those results to know that we are stopping the spread or we are preventing more cases.” says the doctor.
Dr. Castillo says while it is easier to get a test than it was a few months ago, the amount of people that need the test or are worried that they have COVID-19 is creating a tremendous volume for labs.
Dr. Castillo adds the long wait times to get tested and the long times for results is discouraging and those delays in essence are creating a shortage.