Suzanne Walters had been ill for more than a week when she went to a Grand Rapids emergency department on March 19 feeling like she couldn’t breathe.

A classic case of COVID-19, said her doctor, who put the 57-year-old Sparta resident in a unit with other coronavirus patients.

Walters, who said she doesn’t have any pre-existing conditions and has never before been seriously ill, spent five days at Spectrum Butterworth Hospital. Walters said her lung function was so bad that she was asked whether she wanted to sign a do-not-resuscitate order.

But when Walters was tested for COVID-19, the test came back negative. Her doctor shrugged it off, saying coronavirus tests were unreliable -- especially at that early stage of the outbreak.

“She said, 'I believe you tested as a false negative. We’re treating you aggressively for COVID-19,” Walters said.

It’s not an uncommon story in the coronavirus outbreak. Coronavirus tests have roughly a 70% accuracy rate, with about 30% of the tests producing a false-negative result, say experts such as Dr. Jana Broadhurst, a doctor and microbiologist for the University of Nebraska Medical Center.

“It’s a really tough thing,” Dr. Dennis Cunningham, a Flint infectious disease specialist for McLaren Health Care, said about the rate of false-negatives. “I’ve been telling physicians at McLaren if it looks like it might be COVID, assume and treat like it’s COVID" even if the patients tests negative.

False-positives aren’t generally problem because the tests are looking for viral RNA, experts say. But the tests can result in a false negative if the test is administered too early in the illness before there’s enough viral RNA to be detected or if a bad test sample is submitted.

People typically are tested for coronavirus with a nasal swab. But with the big push for mass testing, oftentimes those samples are being collected by people who may lack experience in nasal swabs and/or collecting the specimen in a less-than-optimal settings, such as swabbing a patient through a car window.

When the nasal swab isn’t done properly, it compromises the lab results, Broadhurst said. “We have a mantra in our lab: Garbage in, garbage out.”

In addition, there are variations in the quality of the test kits themselves, which are being produced by about 30 manufacturers, and the labs processing the samples.

“Part of the challenge in testing right now is that because it’s an all-hands-on-deck situation, the (U.S. Food and Drug Administration) just kind of said, ‘OK, go for it’ " in terms of test manufacturers and labs processing the tests, said Dr. Matt Longjohn, a Kalamazoo doctor who works as a public-health consultant. “We haven’t done the validation studies on each of these labs and each of these tests.”

Even when the tests are high-quality, there can be issues. One of the most popular tests now is one produced by Abbott Laboratories that can give results in 15 minutes. But it turns out that storing samples in a special solution known as viral transport media can invalidate the Abbott results.

Cunningham and Dr. Matthew Sims, an infectious disease specialist for Beaumont Health in metro Detroit, both said they think the accuracy of the coronavirus tests has improved in recent weeks.

“There’s no such thing as a perfect test,” regardless of what it is for, Sims said. “Every single test has false positive and false negatives; they’re just going to happen. The issue with the (coronavirus) tests is there were some tests they tried and didn’t work at all or didn’t work well. But the tests being used right now are good tests.”

At this point, Sims said, “the issue is the sampling, which may be problematic. You have to do this nasal pharyngeal swab and you have to get it right. But even if you do it right, there are times when we think the virus actually descends more in the lung than the upper respiratory area and maybe (a swab) won’t find it at that point.”

Yet another issue, is making sure the test is conducted at the right time, Sims said. “The maximal shedding of virus seems to be from a couple of days before you’re symptomatic to a couple of days after you’re symptomatic.”

The importance of getting a good sample is why Cunningham is cautious about a new at-home coronavirus test called Pixel being sold by LabCorp. Patients can collect their own samples using a special nose swab provided in the kit and then send it in to the company’s labs for analysis.

“The ability of the test to detect the virus really depends on the quality of the specimen,” Cunningham said. “A light touch of the swab to the nostrils may not be adequate. The virus is at its highest concentration in the nasopharyngeal space,” where the throat meets the nasal cavity.

“I worry people with symptoms may test negative,” he said about the at-home test. “This may give false reassurance that there is no infection. I’m supportive of increased testing, but I’m not sure this is the right way to proceed.”

Even with the issues involving coronavirus test accuracy, there’s a widespread push to increase testing, which is seen as necessary to get a better handle on the COVID-19 outbreak.

“We want to get more people tested," Gov. Gretchen Whitmer said during her April 17 press briefing. “We need to get people tested in Michigan.”

The state is ramping up the number of sites to obtain coronavirus tests, and Walmart, Walgreens, CVS and Rite Aid are all opening or have opened rapid testing sites to increase testing capacity. To locate testing sites near you, visit Michigan.gov/CoronavirusTest. Most sites ask that individuals contact them first to schedule an appointment.

Meanwhile, Walters is still struggling to recover. Four weeks after her release from the hospital, she said she is still struggling to catch her breathe and her doctor says it’s possible she’s experienced permanent lung damage.

One downside of the negative coronavirus test, Walters said, is that she doesn’t qualify for the waiver of insurance co-pays and deductibles being granted to COVID patients. The test result also means that she’s not counted in the state’s coronavirus statistics.

“My doctor said, ‘You wouldn’t be counted as a COVID death. You’re not going to counted as a COVID survivor,’” Walters said. “I’m not one of the coronavirus numbers, even through I was in a hospital for five days, near death.”

PREVENTION TIPS

In addition to washing hands regularly and not touching your face, officials recommend practicing social distancing, assuming anyone may be carrying the virus.

Health officials say you should be staying at least 6 feet away from others and working from home, if possible.

Carry hand sanitizer with you, and use disinfecting wipes or disinfecting spray cleaners on frequently-touched surfaces in your home (door handles, faucets, countertops) and when you go into places like stores.

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