Abbott plans to ship 4 million coronavirus antibody tests by end of April

An American health care company hopes to ship millions of coronavirus antibody tests across the country in hopes of helping both researchers in finding a treatment and public health officials in understanding the disease.

Abbott announced Wednesday that the company is applying for Emergency Use Authorization with the FDA for a new laboratory-based antibody blood test.

The company said it will begin shipping Thursday and intends to have 4 million tests in laboratories by April and 20 million by June.

This new test could detect the presence of the virus, which can help support the development of vaccines and let public officials understand how widespread the outbreak is, the company said.

Politicians and public health authorities alike warned that easing restrictions in the U.S. and Europe will have to be accompanied by widespread antibody testing to see who might be immune and ramped-up tracing of infected people's contacts with others.

At the moment, trials are underway coast to coast. In Los Angeles County, California, for example, COVID-19 antibody testing started at six drive-thru sites over the weekend. Around 1,000 pre-selected participants, who were selected based on a random sample, will be checked for immunity against the virus.

One of the country's biggest trial yet is taking place in Beaumont Health in Michigan, where 38,000 workers across the health care system will have the chance to get tested.

"This is 100% voluntary, but from the reaction I've seen, most people want to do this, most people want to know. One of the most amazing things yesterday, I was by the blood draw station, and one of the people just turned, saw me and just he couldn't shake my hand but he kind of did a little bow and said, 'Thank you for all of this. You're trying to save us.' I was just awed by that," said Dr. Matthew Sims, director of infectious diseases research at Beaumont Health.

Dr. Jen Ashton, ABC News' chief medical correspondent, said the medical community hopes to answer many questions from this study.

"It's really about the who, what, where, when, how," she said. "We hope to learn who develops antibody, whether people who have mild or no symptoms at all can develop antibodies, when they're developed, how long they last, how powerful they are. All of that is going to be critically important information to help us fight this virus moving forward."