Colorado’s COVID hospitalizations rise slightly for a second week, but other measures are stable

Colorado’s COVID-19 hospitalizations ticked up again this week, but other measures don’t point to a building wave.

As of Tuesday afternoon, 185 people were hospitalized with COVID-19, which was a slight increase from 171 a week earlier. Since July, between 66% and 70% of COVID-19 hospitalizations were primarily for the virus, with some variation from week to week.

New cases dropped, however, with 4,263 recorded in the week ending Sunday — roughly 300 fewer than in the previous week. About 5.7% of tests came back positive over the last seven days, which is essentially unchanged from the average a week earlier.

The number of outbreaks listed as active in Colorado dropped to 175, from 201 a week earlier. The Colorado Department of Public Health and Environment is only reporting clusters in certain medical settings, child care centers, homeless shelters and correctional facilities.

As of Wednesday, wastewater from eight utilities showed increasing amounts of the virus; 19 showed decreases; and 27 had essentially stable virus levels. For the state as a whole, wastewater concentrations are trending down, said Bailey Fosdick, an associate professor of biostatistics and informatics at the Colorado School of Public Health.

Overall, the data suggest a “low plateau” in infections, Fosdick said. Typically, wastewater concentrations and positivity rates rise, with cases, hospitalizations and deaths following. It appears that in this case, however, it may just be chance that hospitalizations are higher on some days, she said.

“We’ve just seen things bouncing around a bit without any clear idea where they’re going,” she said.

The best guess is that Colorado’s hospitalizations will start dropping again and continue to do so for most of the next two months, assuming a new variant with the wrong combination of mutations doesn’t become dominant, Fosdick said. The virus will continue churning out new versions, because that’s what viruses do, but it only matters for the public if a variant is better at getting around our immunity or has other concerning characteristics, she said.

The Centers for Disease Control and Prevention estimated that BA.5 still accounts for 81% of cases, with BA.4.6 causing about 13% and BF.7 causing 3%. All three are descendants of the original omicron.

BF.7 has had a faster growth rate than BA.4.6 over the last month nationwide, but it’s not clear if it has enough of an advantage to displace its cousins. Early data suggests it’s somewhat better at evading the immune system, but it’s not yet clear if that’s cause for concern, Fosdick said.

The most recent Colorado data, from the week of Sept. 18, showed BA.5 was still firmly on top, showing up in about 90% of sequenced samples. BA.4.6 was found in 7%, and BF.7 only turned up in 0.01%.

All but two counties in Colorado — Costilla and Alamosa — are listed as low risk on the CDC’s community levels, which focus on hospitalizations. On the other hand, more than two-thirds of counties had “substantial” or “high” transmission, based on cases and the percentage of tests coming back positive.

Nationwide, cases and hospitalizations are still dropping, though they’ve risen in parts of the Northeast and the Mountain West, according to data from The New York Times.