The newly-available test-at-home kit provided by LabCorp and others use a less invasive short swab to collect a specimen in the nose or mouth. This makes it easier to conduct test collection and avoid the need for special test collection sites that use highly-skilled personnel, such as BayCare’s drive-thru sites. But the results may be less reliable as the viral load is believed to be usually lower in those areas of the body. And the risk of cross-contamination may also be higher since non-trained individuals may oversee the test collection.
“This option definitely helps expand access to testing,” said Cote. “This provides people with an easy and convenient way of getting tested from the comfort of their own home.”
Reliability: In general, a false COVID-19 positive is rare in viral testing – unless somehow the patient’s sample was contaminated during collection or at the laboratory, said Pieretti. False negatives are more common and can be impacted by all kinds of variables, including the body site where the specimen was collected (there may not be enough viral load present) or, most importantly, when in the infection cycle the patient is. And regardless, results are only applicable to the time of test collection. Patients can end up being exposed to the coronavirus anytime after the test.
“When the virus is in very low amounts, the tests can be less accurate,” said Pieretti. “A very small amount of virus can be harder to recognize and may generate a false negative result. Or, one may see a positive result, followed by a negative, then followed by another positive. This happens for example in patients that are recovering. We don’t know whether a positive result at these late stages correspond with the ability of the patient to spread the virus and infect others.”
Speed of results: Depending on the manufacturer and platform, PCR tests can take anywhere from a couple of hours to more than a day to receive results. Generally, health care providers such as BayCare have reserved “rapid-test” platforms for their hospital settings, so acutely ill patients can be diagnosed quickly and treated efficiently. BayCare processes most tests in-house, through BayCare Laboratories. When test demand is high, BayCare send specimens collected from drive-thru testing sites to commercial laboratories for processing. When a patient receives test results is also dependent on how long it takes a lab to process the samples, including patient registration and specimens transportation – which can significantly add to the turnaround times.
Antibody testing is used to learn if someone has had a past infection – it is NOT a diagnostic tool. An antibody test helps determine any presence of antibodies, which are specific proteins the body produces to fight off a COVID-19 infection. Scientists still don’t know if the presence of antibodies help protect the patients from being infected a second time, but it does identify individuals to help in the donation of convalescent plasma for current COVID-19 patients. At BayCare, patients are required to have a doctor’s referral to obtain an antibody test.
For the plasma donations, donors must meet certain criteria to donate blood but do not need a doctor’s note. For more information, potential donors can contact OneBlood at 1-888-936-6283 and select option 9 or visit their website here.