A key performance indicator for an antibody test is its ability to correctly identify antibodies that are not present (sensitivity), and when it correctly detects antibodies that are present (specificity)

It helps to ensure that someone with COVID is positive and someone without have it gets negative results.

The new study found that a urine-based anti-body test had a higher sensitivity (94%) than serum-based (blood-based) COVID tests (88%). Both tests were 100% specific. 1

Marc Sala MD is a pulmonary and critical-care specialist at Northwestern Medicine Comprehensive CoVID-19 Centre. He said both types of antibody tests were equally accurate in the study that used blood and urine samples from hospitalized and unhospitalized patients.

What about other Coronaviruses?

Because SARS-CoV-2, which is not the only coronavirus that can infect humans, has limitations to the urine test currently

The researchers have not yet tried the urine test using samples from patients with infections caused by other coronaviruses, which means they cannot rule out the possibility of cross-reactivity--meaning the antibodies were from another virus, not COVID.

Pills:

buy ivermectin for humans | ziverdo kit | hydroxychloroquine | ciprofloxacin dosage | plaquenil

Potential benefits of Urine-Based Antibody Testing

Although serum-based (blood-based) antibody tests are precise and have a low incidence of complications, a urine-based test could still prove useful for patients and providers.

Beth Oller MD is a family physician at Solomon Valley Family Medicine. She explained to Verywell that urine, unlike blood samples can be collected by patients themselves and doesn't require a trained phlebotomist.

Because urine samples are easier to store and handle than blood samples, they can be useful for clinical practice. A urine-based test would be cheaper than a blood one if you self-collect the sample.

This is a very exciting development as it could mean that other infections and viruses can be tested in the same way.

Oller stated that urine-based COVID antibody testing has the advantage of being less invasive than blood draws.

Sala said that non-invasive urine tests would be beneficial for children because it is difficult to obtain a sample from them.

You Can't Get a Urine COVID Antibody Test--Yet

Despite promising results, the market is not ready for urine-based COVID antibodies tests.

Sala stated that the findings of the study, which was based on a small sample, would need to first be confirmed in a larger group because some aspects are still unclear to researchers.

Sala stated that providers should know whether the antibody levels in patients' urine fluctuate in the same way as the blood antibodies. Also, they need to know if kidney function can affect the results.

Oller stated that the FDA authorization would be required if the goal was to make the test available for commercial use at-home. A emergency use authorization (EUA) will likely be issued first.

You can also request a urine test at any laboratory, walk-in clinic or provider's office.

Oller stated, "Overall this is exciting because it could very possibly mean that there could be methods to test for antibodies for viruses and infections in the same way." It could make some testing easier by using urine tests instead of blood tests. This could also make testing cheaper.