Hawaii Antibody Tests Suggest Community's Level Of Exposure Low

May 19, 2020

Updated: 5/19/2020, 9:06 a.m.

As more people in Hawaii take the COVID-19 antibody test, their results are providing information about how far the virus has spread statewide. While an antibody test cannot determine if a patient is currently sick, it can detect if someone had been infected by showing if someone has the antibodies produced after exposure to coronavirus.

While the tests are not widespread enough to be definitive, available results are indicating that Hawaii's exposure to the virus has been minimal, helped by the stay-at-home orders imposed in March by the state and counties.

Dr. Kaohimanu Dang Akiona, a family care physician with Premier Medical Group Hawaii, has been screening patients for the antibodies on the Big Island. The antibody testing program screened only health care providers at first, but it is now open to the general public.

“This is the process that we would ideally be working with the Department of Health, but we’re not because it's so tenuous, with the state,” she said. "I think the community is helping us kind of work through this process. How do you identify the antibody positives? How do we count them and how do we make our collective knowledge stronger?"

Premier Medical is led by Dr. Scott Miscovich, who has been vocal about the need for robust COVID-19 testing. Premier began offering the antibody tests on May 6th. The medical group uses one of the few tests considered reliable and that is allowed by the federal Food and Drug Administration under an emergency use authorization.

The state health department has been less than enthusiastic about antibody tests. Officials said in a statement that the tests are still being investigated and shouldn’t be used to make decisions on issues such as returning to work or about social distancing.

Akiona says these blanket statements from the department don’t differentiate between reliable tests and unreliable ones and undermine what Premier is trying to do: get more information about people in the community who have been infected with COVID-19.

Because those who have been infected can be asymptomatic, the antibody tests can answer the question whether someone may have had the virus.

Clinical Labs of Hawaii has been working with Premier Medical and reports its testing results to the health department electronically. But only results from the regular COVID-19 swab tests that turn out positive get added to the statewide daily count.

Because the antibody tests can shed light on just how much infection may have gone undetected, Hawaii Pacific Health recently conducted voluntary antibody testing on its health care employees.

About 4,000 Hawaii Pacific Health employees volunteered to take the test. So far, about 3,300 tests have been processed. Only .05 percent have come back positive for antibodies. 

Dr. Melinda Ashton, an executive vice president at Hawaii Pacific Health said that percentage is very low.

"I've never been in that camp that thought there was a lot more virus out there that we just weren't finding and the antibody results being this low tells us that that's probably true," said Ashton.

"Because all of our employees are also members of our community ... I think we've got a good snapshot of what this community has experienced, which is a very low level of circulating virus."

While Ashton is glad that COVID-19 isn’t spreading in her hospitals, the low number raises some concerns. One is that not many of us have developed antibodies, so we’re nowhere near achieving what’s known as herd immunity.

"It takes something like 60 or 70% of the population to be immune to a disease before you start to see herd immunity. And we don't actually know if antibodies to COVID-19 are protected. But there is this sort of hope that at some point, we'll all be immune enough that this disease will go away," Ashton said.

That’s one of the problems Tim Brown, an infectious disease expert at the East-West Center, sees with using antibody tests in Hawaii. 

"The level of exposure in the community is still comparatively low, which means what you pointed out with Hawaii Pacific Health, they found a very low positive rate. And, you know, in some ways, that's good news, but it's bad news if you're hoping that the community was gonna kick in and protect your people," he said.

However, Brown said herd immunity alone would probably not work in a place as large as the United States because the death toll would be far too large.

Even hard-hit places in New York only have about 20% of people testing positive for antibodies, far from the 60% needed for herd immunity. That’s why he predicts that while we wait for a vaccine, a more likely scenario will be that doctors will find better treatments for COVID-19.

“We're not going to be doing much for the next year, year-and-a-half, until there's a vaccine,” he said. “I think actually, probably, the more likely thing is we'll find some decent treatments and get enough experience with treating this, that it becomes a less lethal disease -- not because the virus has changed, but because our knowledge of treating things has improved.”

As for using the antibody test to identify people who were possibly infected with COVID-19 before testing became available in mid-March, it’s unlikely to produce results. 

“I'm sorry, those people who think they had it in January and February. No, you didn't have it in January and February,” he said. “Had it happened, we would have seen a spike in deaths at that time, which we did not see, which means it wasn't a novel coronavirus that was circulated at the time. It was probably a common cold.”

Although there may not be much COVID-19 circulating in the community, Brown says we shouldn’t let our guard down.

He said with some less contagious diseases, it’s enough to get the infection down to a very low number. But with the coronavirus as transmissible as it is, one person’s cough can infect many, many people.