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The official tally of confirmed cases of COVID-19 in Utah stands at 602. The actual number of people infected however is considerably higher.

That’s because of a group of people the state calls “presumptive positive.” These are people epidemiologically linked to a person who actually tested positive.

As Angela Dunn, the state epidemiologist explained, these are cases where someone has been in close contact with someone who has tested positive, say a family member, and then develops symptoms.

“We wouldn’t test them, we would just assume they have COVID-19 and recommend quarantine until their symptoms resolve,” Dunn said. Those figures are tracked but are not included in the daily report of the state’s COVID-19 cases.

As of Friday morning, the Salt Lake County Health Department had identified more than 70 of these “presumed positive” cases, in addition to the tested cases, according to Nick Rupp, spokesman for the department. At the time, there were 202 lab-confirmed cases. That number has since climbed to 279.

At least two of those “epi-linked” cases happen to be friends of mine, a couple who don’t want me to use their names.

One friend was contacted by the health department after a co-worker tested positive. Each morning after that, the health department would send a text message asking if symptoms had developed. Once symptoms showed up, a case worker called for an interview and my friend was told to quarantine.

The next day, her husband started getting the same texts and eventually developed symptoms of the disease.

Right now it looks like they’ll both be OK. Experts say that four out of five people who get the disease don’t end up needing to go to a hospital.

The point is: There are a lot more people who have been infected with this disease than the official reported number counts, and the state knows that.

Tom Hudachko, spokesman for the Utah Department of Health, said the state doesn’t have a figure for the “presumed positive” cases because the Centers for Disease Control and Prevention hasn’t issued a uniform definition or criteria for how to treat those cases, so how they are tallied and treated varies from health department to health department.

But the figure matters, because if the Salt Lake County numbers hold true for other parts of the state, a third of the cases that health officials know are out there are not being reported to the public and that the number of people actually infected with the coronavirus is at least 670 and could be closer to 800, not the 602 reported in the official numbers.