Colorado has surpassed yet another grim milestone in the nearly two-year COVID-19 coronavirus pandemic: 10,000 deaths.

As of Tuesday, the state counted 10,018 deaths due to the novel coronavirus. A surge of new cases in the past few months has led to higher daily COVID-19 deaths, pushing the number of lives lost past 9,000 less than a month ago, and past 8,000 a little more than two months ago. Previously, it had taken the state more than three months to move from 7,000 to 8,000 deaths.

“This is largely a pandemic of the unvaccinated; with the arrival of the contagious variant delta, the unvaccinated are at extremely high risk of hospitalization from COVID,” Conor Cahill, a spokesperson for Gov. Jared Polis, wrote in an email responding to the latest death toll.

“If we did not have over 70% of adults vaccinated when the delta wave began hitting our state and region this fall, the impacts of deadly variant would have been far more devastating, and our health care system would have been destroyed.”

Tuesday also marked the one-year anniversary of the vaccine’s arrival in Colorado, when Polis greeted a delivery truck at the door of the state health lab. The number of weekly COVID-19 deaths began to fall gradually after that point, as the winter 2020 surge subsided and vaccines began to flow to the state’s most vulnerable populations.

But the latest surge has once again inflated them to levels unseen since the beginning of 2021. The highest death rates in recent months have been in areas of the state with the lowest vaccination rates. For example, in Dolores, Kit Carson and Washington counties, where more than half of the residents are still unvaccinated, the number of per capita COVID-19 deaths between May and early December is seven times higher than in Denver and Boulder counties, where the unvaccinated portion of the population is closer to 10%, and around 20 times higher than Pitkin County, where almost every resident has had at least one dose of a COVID-19 vaccine.

When age-adjusted, state health department data show unvaccinated people are 10 times as likely to die from COVID-19 than fully vaccinated people.

Beth Carlton, an epidemiologist with the Colorado School of Public Health, said this week that the delta variant has “extracted a devastating toll on the unvaccinated.”

“While we don’t fully know what lies ahead with regard to omicron,” she said, “it seems likely that communities with low vaccination rates will bear the greatest burden of COVID – in terms of lives lost and hospitalizations.”

COVID-19 vaccines have been available for most adult Coloradans since April, and roughly two-thirds of the state’s population is fully vaccinated. In areas below the statewide average, though, the death rate is almost three times the rate of areas with a larger portion fully vaccinated. 

At times during the pandemic, which took hold in the U.S. in March 2020 and the effects of which has ebbed and flowed in the 21 months since, the novel coronavirus has been the leading cause of death in the state, as it has been again for the past two months, outnumbering deaths caused by cancer and heart disease.

The current surge in COVID-19 cases, hospitalizations and deaths began in late summer and has been on the wane in the past few weeks, with cases and hospitalizations beginning to subside. But the number of daily COVID-19 deaths remains elevated, as the disease usually leads to death only after several weeks, meaning deaths associated with a surge in cases lag by weeks.

The United States hit its own nationwide milestone Dec. 15, surpassing 800,000 total COVID-19 fatalities, according to the Associated Press. More Americans have died of the virus since it first emerged than live in four states and Washington, D.C. Four hundred and fifty thousand of those deaths have come in 2021 alone. While Colorado needed roughly two months to jump from 8,000 to 10,000 fatalities, the United States took 73 days to move from 700,000 to its latest milestone.

The Associated Press and Reuters contributed to this report. 

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