COVID-19 Antibody Tests

We had hoped that with summer we would see the end of this COVID-19 wave of infections, but unfortunately it appears that will not be the case. Neverthless, very few pediatric patients have been swabbed/tested so far. Now that there is an antibody test, people want to know if they or their child might have had the infection when they had some illness earlier this year but were never diagnosed.

The antibody test involves drawing blood from the patient’s vein. The test that is available is only 60% sensitive, meaning that only slightly more than half of the people who truly had the disease will be positive. So a negative test cannot really be trusted. A positive test might indicate that the person had the infection at some time in the past but again the test cannot be trusted completely. There can be false positive results too. Where the rates of COVID-19 are relatively low, as in Pima County, the likelihood of a false positive antibody test is higher, so there's actually about a 50% chance that a positive test result is incorrect. Additionally, a truly positive test does not indicate when the person was infected and there is not enough evidence to show that having the antibodies provides any sort of immunity.

So, should your child get antibody testing for COVID-19? Our opinion at Mesquite Pediatrics is:  probably not.

For more information about the COVID-19 tests:

https://www.aappublications.org/news/2020/05/22/covid19antibodies052220

Susan McMahon, MD