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ARUP Laboratories, a national reference laboratory located at the University of Utah’s Research Park, has announced that they have begun COVID-19 antibody testing in Utah.

Utah Lt. Gov. Spencer Cox hailed the news as a “really big and exciting announcement,” one that will “help ... make better decisions and get people back to work much sooner.”

Really big and exciting announcement today! It’s going to take a few weeks to ramp up, but this is the 2nd critical piece of testing we have been working on. It will help us make better decisions and get people back to work much sooner. 👊🏼👏🏼 https://t.co/vb7XCcG0IG — Spencer Cox (@SpencerJCox) April 12, 2020

When someone is infected with the novel coronavirus, their body’s immune system begins to create antibodies, cells that work to prevent future infection. ARUP’s test looks for the presence of these antibodies. A positive test would signal that someone has already had COVID-19, even if they remained asymptomatic.

Whether someone who tested positive for the presence of antibodies would likely be immune to COVID-19 is an unanswered question with this particular disease, according to tweets from Julio Delgado, the chief medical officer at ARUP. Those studies are ongoing, he said, and immunity may depend on the quantity of antibodies produced by the immune system in question.

Ray Firszt, an allergist-immunologist in Utah, told FOX 13 that he was optimistic about immunity.

“We believe that if you’ve been infected and you recover, and you develop IgG antibodies, so the memory antibody, that you are effectively immune to the virus. Which means you cannot get it again if you are exposed ... and you’re not contagious to someone else,” he said.

Antibody testing on a large scale can also give critical information to epidemiologists who want to understand how the coronavirus is spreading throughout a community. Standard testing protocols only measure those who were most sick — or most fortunate to get a test — and therefore miss sectors of spread within the state.

In high enough quantities, these tests can make clear how many people truly are infected with the virus, information the state can use in determining whether to continue policies like stay-at-home directives.

The tests aren’t available in great numbers right now, but ARUP is ramping up production. The plan is to increase testing capacity to support testing to the general public “in the next couple of weeks,” not just locally in Utah, but nationwide.

In the meantime, Delgado said that the first to receive the test should be health care workers, to “try to determine if they have become infected with the virus and likely developed immunity in case they have not presented symptoms."