Colorado can expect more COVID, respiratory illness in near future

Colorado likely will experience a rise in COVID-19 and other respiratory viruses in the coming weeks, but the state isn’t expected to see major challenges to health care capacity.

Nationwide, wastewater data suggests COVID-19 is more widespread than it has been at any point since January 2022 — the tail end of the first omicron wave. Hospitalizations are significantly lower than they were at that time, though they have reached their highest levels since mid-January 2023, according to the Centers for Disease Control and Prevention.

COVID-19 hospitalizations also have ticked up in Colorado, with 246 people receiving inpatient care for the virus as of Tuesday, compared to 213 a week earlier. Tuesday’s total was within single digits of the number hospitalized at the same time last year, but only one-sixth of what it was in January 2022.

Given the national trajectory, Colorado most likely is entering a period of increasing infections, said Cathy Bradley, dean of the Colorado School of Public Health.

Wastewater data showed virus concentrations were rising in three-fourths of watersheds in the state as of Wednesday, with one showing a decrease and the rest roughly flat.

Experts aren’t sure how much of the current increase in infections is due to changes in human behavior, such as travel and holiday gatherings, and how much comes from the JN.1 variant, which accounts for about 62% of current infections in the U.S. and is the first to establish a clear dominance over other versions of the virus in months.

JN.1 is better at reinfecting people with some existing immunity than previous versions of the virus, but it doesn’t appear any more likely to cause severe illness.

Since most people now have some immunity to COVID-19, a smaller percentage of cases result in hospitalization or death than did earlier in the pandemic. Still, the virus can be severe, particularly for people with other health problems, and can lead to long COVID symptoms that persist for months or years.

The CDC reported about 1,600 people died of COVID-19 in each of the first two weeks of December, which were the most recent period with full data. That’s about one-sixteenth of the toll from the virus in the worst week of the pandemic, but still almost 10 times the number of people who died of flu during those weeks.

People who haven’t gotten their seasonal flu shot or updated COVID-19 vaccine should do that as soon as possible, Bradley said. Masks, handwashing, staying home while sick and improved ventilation reduce the odds of spreading the virus, while antiviral medications can prevent severe illness in high-risk people if taken early enough. Some of the same measures also can prevent flu and respiratory syncytial virus.

Hospital admissions for flu in Colorado appear to drop in the most recent week with data, which was the week ending Dec. 31. In that week, 278 people entered hospitals for flu, down from 340 the previous week. Sometimes apparent drops disappear as late reports come in, though, so disease watchers will need to see multiple weeks of declining hospitalizations before they declare the flu season has peaked.