A virologist's search for answers: Curious case of 'cryptic COVID' leads to Columbus area

A virologist in Missouri studying wastewater data in order to analyze the spread of the virus that causes COVID-19 is looking for someone he says has had the disease for two years but doesn't know it.

That search has led him straight to central Ohio.

Marc Johnson, a professor of molecular microbiology and immunology at the University of Missouri School of Medicine, has traced what he calls a unique strain of the novel coronavirus to two locations: Columbus and Washington Court House.

He thinks it's from one person who lives in Columbus and travels to Washington Court House, presumably for work, and it's getting worse. May data shows the Fayette County city of 15,000 people experienced its highest COVID wastewater levels to date, comprising entirely the cryptic lineage.

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"This person was shedding thousands of times more material than a normal person ever would," Johnson said Thursday in an interview with The Dispatch. "I think this person isn't well. … I'm guessing they have GI issues."

But it's not the first unique mutation Johnson and his team have found.

In January 2022, the team also identified a unique strain in Wisconsin, which it traced to a single facility that serves about 30 people, according to the team's latest manuscript, which it published May 17.

The company offered free tests to employees, but those who tested all came back negative, Johnson said. After 13 months, the lineage suddenly vanished in January.

"We don't know if that person quit (their job at the company) or got better," he said.

The Ohio lineage is the 36th unique strain the team has found, with a 37th recently discovered in the Bronx.

Unlike other researchers, Johnson's team does its sequencing differently than others by sampling only a small piece of the genome, he said.

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A spokesperson for Columbus Public Health said the agency didn't have any information about the lineage and referred questions to the Ohio Department of Health and the Centers for Disease Control and Prevention.

In a statement Wednesday to The Dispatch, the CDC said it is aware of Johnson's investigation and is working with him to learn more.

"The virus lineage in question is not currently spreading or a public health threat," according to the statement.

"Unusual or 'cryptic' sequences identified in wastewater may represent viruses that can replicate in particular individuals, but not in the general population," according to the CDC. "This can be because of a compromised immune system. CDC and other institutions conduct studies in immunocompromised individuals to understand persistent infection and virus evolution."

A state health department spokesperson said the agency is aware of Johnson's research but because the strain hasn't spread beyond the two sewersheds in two years, health officials don't consider it a threat to public health.

In addition, because the genetic sequences are fragments, they can't be matched to a particular individual, according to the ODH spokesperson. For that reason, it's impossible to say for sure whether they're from a single person — or even from a human, as opposed to, say, an infected animal in the sewershed.

Is there a danger of widespread infection in Ohio?

Although the risk of spreading the mutated virus is low — none of the 37 lineages Johnson's team has identified have done so — it could pose serious health complications for the person who is carrying the virus, Johnson said.

Of Columbus' 650,000 units in the sewershed, the individual accounts for half of that, which amounts to "probably a few trillion virus particles a day" or "several cubic feet of cells," Johnson said.

"I don't know of any virus that chronically sheds that much material that isn't hazardous over the long haul," he said.

If left undiagnosed, Hepatitis C, for example, can result in the shedding of large amounts of viral material but often ends in liver cancer, he said.

What should you do if you think you might be the source of the Ohio cryptic COVID lineage?

Do you live in Columbus and occasionally travel to Washington Court House for work? Have you experienced GI issues for the past two years?

If so, you could be the source of the cryptic COVID lineage in Ohio.

The first thing you can do is test yourself for COVID. But because this lineage is likely limited to the GI tract, a conventional nasal swap might not yield a positive result, Johnson said.

Most rapid antigen tests are not specifically designed to test stool, though at least one — Corona-Ag by DyonMed — is, Johnson said.

Citing the instructions, either mix a matchhead-sized sample with the buffer solution provided or swab the wastewater and mix it with the buffer. If you test positive, ask someone else to test their stool, just to make sure it's not a false positive.

How can identifying the source of a cryptic COVID lineage help researchers?

Identifying the individual could help researchers better understand how mutated versions of the virus work and identify which ones to keep an eye out for becoming the next widespread variant to take off.

It also could lead to the creation of better, more targeted vaccines in a timelier manner, Johnson said.

"We would like to understand who are the people who can get these chronic infections, and is there something we can do about it?" he said.

nshuda@dispatch.com

@NathanielShuda

This article originally appeared on The Columbus Dispatch: COVID in Ohio: Sewer data led scientists to Columbus, Washington CH