Rather than answering questions about how COVID-19 has spread through communities and informing decisions to end lockdown orders, antibody testing is sometimes muddying the water further.
The Wall Street Journal reports that some people have received unclear results. It notes, for instance, that some people who have tested positive for antibodies recall being ill far before there was any evidence of COVID-19 in the US. Others, it reports, like Kelly Flores from northern Virginia, have tested both positive and negative for antibodies on different tests.
"It's such a load off your mind if you know you've at least had it once," Kelly Flores, who is awaiting results from a third test, tells the Journal. "It's just frustrating to not 100 percent know for sure."
As Kaiser Health News reports, there are some 100 antibody tests available in the US, but concerns have been raised about some of the tests' reliability. The Food and Drug Administration earlier this month required antibody test developers to seek Emergency Use Authorization and provide validation data.
But KHN adds that even a reliable test will give false positives. For instance, it notes that if an area has a 4 percent infection rate and an antibody test has 95 percent accuracy, testing will give nine positive results for every 100 tests conducted and five of those will be false positive results.
"If a person tests positive, what does that mean?" Travis Riddell, the health officer for Teton County, Wyoming, which looked into, but declined, antibody testing, says at KHN. "And is that useful information? We just don't know yet."