Tim Steller's opinion: Sick around gem show time? It probably wasn't COVID-19

Lots of Tucsonans got sick in late January or early February and have spent the last couple of months wondering if they had COVID-19.

The culprit everyone points their finger at: The gem show. The annual Tucson Gem, Mineral and Fossil Showcase, which runs for two weeks usually starting in the last days of January, attracts thousands of visitors from all over the world, and we interact with them at restaurants, hotels, theaters, at the shows themselves.

It’s so common that people pass around sicknesses at the show that it’s long been nicknamed The Germ Show.

But thanks to genetic sequencing and antibody testing, we can start to come to a pretty strong conclusion about whether COVID-19 arrived in Tucson then and circulated along with the cash and fossils. The best information so far: It probably did not.

Your sickness, if you got sick then, was probably just a flu or another common illness.

That conclusion comes from a variety of sources. One of the most interesting is the genetic sequencing done by Michael Worobey, a friend of mine who heads the University of Arizona’s department of ecology and evolutionary biology.

By analyzing the genetic mutations of the virus from samples taken in Arizona, Worobey and colleagues can trace back when the initial clusters of infection were happening here. These mutations happen in the novel coronavirus at a pace of one every two weeks, he said.

“We have evidence that if you’re as generous as possible, there could be an Arizona cluster that goes back as far as mid-February,” he said. “We think later February and March is more likely for when the first productive transmission clusters got started.”

This year, the gem show began Jan. 30 and ended Feb. 14.

Any illnesses from mid-February back into early February or January are very unlikely to have been COVID-19, Worobey said.

“People who say their aunt had the worst flu-like illness in January and is sure she had COVID — not very likely,” he said.

That’s interesting not just because it dumps cold water on the widespread hopes or fears (depending on how you look at it) that COVID-19 was here early, but also because it highlights a success, Worobey noted.

The first novel coronavirus infection in Arizona was diagnosed on Jan. 26 — one of the earliest in the country. But the infected man, who had returned from Wuhan, China, to Arizona State University, went into isolation and apparently did not start an outbreak. He was released from isolation after 26 days and multiple negative tests.

Still, a lot of people got sick in those late weeks of January and early weeks of February, and most likely it was flu.

Flu-like illness was more prevalent in Arizona’s hospital emergency rooms than COVID-19-like illness until the week of March 22, Arizona Department of Health Services data shows. Flu was much more common until late February, when COVID-like illnesses started to rise.

Now, with the arrival of plentiful antibody tests, people who were sick in late January and early February have been able to find out if they have antibodies to the virus. If results are accurate, a positive antibody test would show that a person was previously exposed to COVID-19 and could be immune to reinfection, at least for a period.

I put out a call via Facebook to find out if any local people who were sick around the gem show had gotten antibody tests. Six people responded that they had been sick at the time and got antibody tests — none tested positive.

Shanna Leonard got sick in late February, just after the gem show, she told me. It was a bad illness, roughly matching the symptoms of COVID-19. In recent weeks she jumped at the opportunity to see if she had antibodies. She didn’t.

The same happened with James Gregory. He was working near the Tucson Convention Center in early February and went to restaurants and bars in the area. About Feb. 15 he got good and sick with symptoms similar to COVID-19, but not exactly matching. In April he got the antibody test, and it came back negative.

He still wonders if the test was accurate, since especially the earlier antibody tests had a lot of erroneous results.

Kevin Dahl and his son Brian Dahl had similar experiences — sick around the gem show. Brian had a direct connection to the show, though: He was driving for Lyft and incredibly busy, doing 30 to 40 rides for a six-hour shift, and got sick near the end.

Father and son got tested together at the UA, and Kevin’s test came back negative, but Brian’s came back “indeterminate,” which can mean basically anything, according to the explanation Brian Dahl received.

But while the gem show probably did not start a coronavirus outbreak in Tucson, another key local festival could easily have, if it hadn’t been canceled, Worobey said.

Remember early-mid March, when everyone was starting to reconsider plans? In Tucson, the big question was the book festival, which was canceled less than a week before it was scheduled.

Worobey concludes from his research, “If the book festival had gone forward, it’s a no-brainer that it would have led to the deaths of lots of Arizonans.”