Dene Callas, an advertising executive in Santa Monica, Calif., quickly accepted when her doctor offered to test her this month. An initial rapid test was invalid; a second one came back negative. Still, Ms. Callas believed she had contracted the virus and recovered: She had attended a conference in Las Vegas in January and fallen ill within days. A positive test, she said, would have made a difference. “I would be a little braver outside,” she said. “I would be out there volunteering if I knew I had the antibodies.”
Some large employers, including Goldman Sachs and Twitter, have looked into antibody tests but not bought any. Amazon has not focused on antibody screening, though it intends to roll out diagnostic testing for the hundreds of thousands of people in its warehouse and logistics network, according to people familiar with the plans.
Some smaller businesses, though, have pursued the new tests. At John Christner Trucking, a food transportation company near Tulsa, Okla., about 220 workers took rapid tests. They were concerned about exposure after two were infected with the virus. A small number came back positive, said Danny Christner, the chief executive. “I knew it wasn’t a silver bullet, but it was some information that people could be aware of,” he said.
The Chicago Public Health Department bought 5,500 rapid tests and put them to use in homeless shelters as a supplement to diagnostic testing. Those who were positive for the early antibodies were placed in hotel rooms rented by the city during the 48 hours it took to get diagnostic test results back, said Dr. Allison Arwady, commissioner of the department. The next step may be testing people in nursing homes, she said.
Sports leagues are also considering how antibody tests can figure into their plans. The N.B.A., with its season paused, has been approached about purchasing tests and is awaiting guidance from public health officials.
Major League Baseball employees and players will be tested as part of a 10,000-person nationwide study run by outside researchers to better understand the scale of infection. A players’ union official said the testing was voluntary and not connected to beginning the season.
In Search of a Test That Works
While political leaders and some health officials say that antibody testing will be essential to reopening the country, it is unlikely to meet expectations anytime soon.