Colorado Avenue in Telluride, ColoradoNick Fox / Shutterstock

San Miguel County in Colorado has, in ordinary times, fewer than three full-time employees in its public-health department. It has no hospital. Its total population is only 8,000. And yet last week, the county became the first in the United States to announce that it would be offering all its residents a new kind of test for COVID-19.

The tests are being donated by United Biomedical, a multinational biotech company whose executives, a married couple, happen to live part of the year in Telluride, the resort town that is also San Miguel’s county seat.

“It’s a small community,” Mei Mei Hu of United Biomedical told me on the phone from Colorado this weekend. “Very small,” her husband, Lou Reese, added. “Whether it’s just getting a donut or walking by on the street or on the ski hill with the ski patrol,” he said, “we know and have met or interacted with almost every member of the medical or emergency community here throughout the course of our lives.”

Hu and Reese—along with Hu’s mother, Chang Yi Wang, who is United Biomedical’s chairwoman—are the founders of the company’s new COVID-19–focused subsidiary, c19. United Biomedical has facilities in New York, China, and Taiwan, and it develops animal vaccines as well as diagnostic kits for human diseases. So when the novel coronavirus first appeared in China, the company started working on testing, and when cases started showing up closer to home, Hu and Reese thought of their community in Telluride. They floated the idea of testing the county to an old family friend, who also happens to be the area’s chief paramedic. Like they said, it’s a small community.

At that point, San Miguel County was, like everywhere else in the United States, having trouble getting tests for every patient who needed one. This particularly worried Sharon Grundy, the county medical officer, because Telluride had so many visitors coming and going. “We’re a high-risk area because we are a resort community,” she told me. (A group of skiers visiting another Colorado resort town, Vail, ended up seeding a coronavirus outbreak in Mexico.) The county was able to test some people through the state health department and a commercial lab, and got its first positive result on Friday. But when I spoke with Grundy on Friday, she also said the whole county had only two swabs left. “It’s not just us,” she hastened to add. “It’s the whole country.”

Without testing, San Miguel County’s health workers would be unable to track the virus’s spread. They would be, to use the words of the World Health Organization’s director-general, fighting “a fire blindfolded.” So United Biomedical’s offer to donate the kits came as a relief. “This gave us some hope,” Grundy said.

United Biomedical’s COVID-19 test is different from those typically being run on nasal swabs collected around the country. Those tests use a technique called RT-PCR to look for the virus’s genetic material in a patient’s nose and throat, but United Biomedical’s test requires a blood draw. It uses a different technique, called ELISA, to look for antibodies, the proteins the immune system makes to neutralize the virus. Antibody tests, also known as serological tests, don’t always pick up early viral infections, but they can tell if someone has ever had a particular virus—maybe even if they were asymptomatic.

For this reason, scientists all over the world have been pushing antibody tests as a way to study the true scope of the coronavirus pandemic. If serological testing can find asymptomatic carriers of COVID-19, it can also clarify the disease’s transmission and fatality rate. Testing a whole population—say, a whole county—would give epidemiologists a snapshot of everything going on in one place. “Any sort of population-based study is really interesting,” says Caitlin Rivers, an epidemiologist at Johns Hopkins University. And while it’s unclear how long immunity to COVID-19 lasts, she says, it could allow people who are immune to go back to their normal lives.  

Hu said that United Biomedical started working on an antibody test back in January, as the outbreak got serious in China. The company had developed a very similar test for SARS in 2004. Its scientists could apply that expertise to COVID-19, but they needed blood samples from COVID-19 patients to confirm that the test indeed detects antibodies against the virus causing the disease. The company’s existing connections to China and Taiwan helped it get patient samples quickly. “We were actually able to ship tests to ground zero in Hubei, Shanghai, Beijing, and Taiwan,” Hu said.

According to data that Hu said the company has filed with the FDA, its serological test was validated using 47 samples from coronavirus patients and began to detect antibodies 10 days after infection. The company also ran the test against hundreds of COVID-19–free samples from blood banks to confirm that it does not mistakenly pick up antibodies for related viruses that cause the common cold. Catherine Blish, an immunologist at Stanford University, told me that other scientists have developed a COVID-19 antibody test that picks up infection earlier, but there is often a trade-off between how specific a test is and how early it can detect an infection. “They managed to get very fabulous specificity,” she said. United Biomedical is now waiting for emergency-use authorization from the FDA, but certified labs can offer testing in the meantime because of the public-health emergency.

Researchers in China, Singapore, Europe, and the U.S. have made their own versions of COVID-19 antibody tests, and several companies are now offering theirs. Florian Krammer, a biologist at the Icahn School of Medicine at Mount Sinai in New York, says his lab started working on one in January, the very day that a Chinese group first shared the genetic sequence of the novel coronavirus. Krammer and his colleagues used that genetic sequence to synthesize S, the protein that makes up the virus’s outer spikes. Any antibody that binds the synthesized S protein is likely the result of a past or ongoing COVID-19 infection. United Biomedical’s test also uses S, as well as parts of two other viral proteins.

Krammer’s group posted a preprint paper describing its test on Wednesday. The holdup, he told me, was getting blood samples from coronavirus-positive patients to validate the test. Otherwise, creating these tests is fairly routine for labs like his. “Serological testing is not rocket science,” he said. The clinical lab at Mount Sinai can already run this antibody test for COVID-19, but he said it will be limited to special cases, such as looking for patients with COVID-19 immunity, whose blood could be turned into a therapy.

The challenge with these tests is scaling up. United Biomedical’s COVID-19 test kits are being manufactured at its facility in New York and shipped to Colorado. In theory, running each test in a lab takes only a few hours. But the samples have to be shipped to another lab for testing, and lab capacity is limited.

San Miguel County is still figuring out exactly how to get the tests to 8,000 people across 1,300 square miles. Ideally, residents would get voluntarily tested twice, two weeks apart, which doubles the logistical challenge. The county simply does not have the manpower to go door to door, so Grundy said it’s planning to set up two testing stations, in Telluride and Norwood, to reach as many people as it can. The county is relying on volunteers, hopefully, to help staff the stations as well.

It’s too early to say how this public-private partnership in San Miguel will work out, but the program is getting started in earnest this week. Reese said several other states and counties are now interested in the antibody test as well. “I would love to see [an antibody] test deployed widely everywhere,” Blish said.

A tiny county with one confirmed coronavirus case may not be the most obvious place to start widespread serological testing, but that’s exactly what is happening in the U.S. The testing debacle has left much of the country desperately short on capacity. Many people with coronavirus symptoms are unable to get tested, although being rich or famous or an NBA player seems to help. The story in San Miguel is that of a small community’s residents looking out for one other in a time of crisis. But it is also a story of how wealth and power—and proximity to them—continue to determine access to health care.

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