Boulder County likely has a low level of community transmission of the omicron variant, a state health official said Tuesday, despite having a confirmed case last week.

Wastewater testing, part of the state’s overall detection and surveillance system, identified possible spread of the new variant, said Rachel Herlihy, the state’s epidemiologist. But she said wastewater provides a “plus-minus system, so detected, not detected,” essentially preventing the state from “quantifying specifically how much.”

“Our feeling at this point is it’s probably a very low level of circulation, a low level of community transmission that could potentially be occurring in Boulder,” she said. “We’re obviously going to be looking closely at additional specimens that come in from patients who seek testing in Boulder to see if we can have detection in our routine clinical testing program.”

Gov. Jared Polis has said he’s not yet “troubled” by the variant’s arrival here, which was considered an inevitability, given omicron’s high level of transmission.

The variant was first identified in Colorado last week, with the first case in Arapahoe County and a second confirmed Friday in Boulder County. No other cases have been confirmed here. Both of those initial patients had recently returned from travel in southern Africa, where the variant was first identified officially and where cases have spiked in its wake.

The wastewater testing is an early warning system, state officials said last week, that gives an overall picture of what strains of the virus are circulating on a community level. The other primary method is random sequencing of 15% of the state’s daily positive tests, which is one of the highest rates of surveillance in the country. For months, delta has been the dominant force here.

The state has also implemented “enhanced case investigations,” Herlihy said, as well as stepped-up travel monitoring.

There’s still much that experts don’t know about omicron, she said, though more robust research should be available in the coming weeks. “Limited data,” Herlihy said, indicates it’s spreading more quickly than the delta variant in South Africa and that there’s a higher risk of reinfection for those who were previously sick.

But hospitalizations don’t appear to be higher than expected in South Africa, she continued, and anecdotal reports from the country indicate many patients are less ill. She cautioned again that the data is limited or anecdotal.

Researchers at Steve Biko/Tshwane District Hospital Complex, a major hospital complex in Pretoria, South Africa’s capital and the center of the omicron outbreak, reported last week that the majority of patients in the COVID-19 ward there were asymptomatic.

Their findings reflect similar trends at hospitals across the province as a whole, leading some infectious disease experts to be cautiously optimistic that omicron may manifest in a milder form of illness. But that analysis relied on 42 patients.

Dr. Anthony Fauci, the chief medical adviser to President Joe Biden, said on Sunday that “thus far, the signals are a bit encouraging.” Most of the patients who developed COVID-19 pneumonia at Steve Biko/ Tshwane District Hospital Complex were unvaccinated, leading to hopes that the strain will not evade the protection given by vaccination.

Regardless of what that data shows, Herlihy stressed that prevention strategies remain the same: vaccines, boosters, masking, distancing, good hygiene.

Data gathered from the state indicates that patients with boosters are 2.4 times less likely to contract COVID-19 than vaccinated residents. It’s starker — 9.7 times — when compared to the unvaccinated. There’s an even larger discrepancy when it comes to hospitalizations: Boosted people in Colorado are 47.5 times less likely to be hospitalized than unvaccinated residents, who account for 83% of the state’s COVID-19 patients.