LabCorp CEO Adam Schechter on Tuesday urged Americans to be vaccinated against Covid-19 and told CNBC that recipients are not being advised to be tested for Covid antibodies afterward.”At the moment, there’s no recommendation to do that. We still have to understand a lot more about the vaccines, know what to measure, how to measure,” Schechter said on “Closing Bell.”The body’s immune system produces antibodies in response to a foreign pathogen and uses them to help fight an infection. Throughout the pandemic, antibody tests have been used to determine whether someone was previously infected with the coronavirus.Now, as Covid vaccines are being administered to millions of people, questions have been raised about the role antibody tests could play in determining whether a vaccine recipient is developing an immune response. In clinical trials, the vaccines from both Moderna and Pfizer-BioNTech were shown to be more than 94% effective in preventing symptomatic Covid-19.In December, for example, Roche was granted emergency use authorization by the U.S. Food and Drug Administration for a test that detects antibodies against the coronavirus’ spike protein. In a press release at the time, the Swiss diagnostics and pharmaceutical giant contended the test could be valuable after someone is vaccinated against Covid.”Many current candidate vaccines aim to induce an antibody response against the SARS-CoV-2 spike protein,” the company said. “Tests that quantify antibodies to the spike protein could be used to measure the level of that response and track that measurement over time.”Schechter acknowledged there could be a role for post-vaccination antibody tests, but he said “there’s still a lot more we have to learn.””In the future, it may make sense to look at antibodies. It may make sense to look at T-cells,” which represent another element of the body’s immune response, he said. “At the moment, as many people should get vaccinated as quickly as possible, and there’s no recommendation to get an additional blood test afterwards,” he added.Shares of LabCorp closed Tuesday’s trading session at roughly $220 apiece. The stock is up more than 120% since its pandemic-era low on March 19 of $98.