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Coronavirus

The data are in: Coloradans who get a COVID vaccine booster are nearly 50 times less likely to be hospitalized

Coloradans who received a booster shot were 2.4 times less likely to test positive for COVID-19 than people who had been fully vaccinated against the virus but had not received a boost

Gov. Jared Polis receives a third and booster dose of the Moderna Covid-19 vaccine about six months following his last shot on Friday, Oct. 22, 2021, at Denver Health in Capitol Hill. “I’m now at full FDA and CDC approval for folks who had Moderna … I'm ready to get the booster because, like most Coloradans, Americans are ready to put this pandemic behind us,” Polis said. (Olivia Sun, The Colorado Sun)
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Coloradans who receive a COVID-19 vaccine booster are less likely to test positive for the coronavirus and, if they get infected, are less likely to require hospitalization, the state’s top epidemiologist said Tuesday as she released data on the efficacy of vaccine boosters for the first time. 

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Between September and November, Coloradans who received a booster shot were 2.4 times less likely to test positive for COVID-19 than people who had been fully vaccinated against the virus but had not received a booster. People who received a booster shot were 9.7 times less likely to test positive for the disease than unvaccinated Coloradans.

The state also collected hospitalization data during the same time frame, finding that Coloradans who received a booster shot were 3.3 times less likely to be hospitalized after contracting COVID-19 than people who had been fully vaccinated against the virus but had not received a booster. 

People who received a booster shot were 47.5 times less likely to be hospitalized after contracting the disease than unvaccinated Coloradans.

A screenshot from a presentation by Dr. Rachel Herlihy on COVID-19 vaccine booster efficacy.

Dr. Rachel Herlihy, Colorado’s top epidemiologist, said the booster shots are having “a clear impact in protecting people.”

All Colorado adults are eligible to receive a COVID-19 booster shot. So far, 41% of eligible Coloradans have received one. 

Gov. Jared Polis, speaking at a news conference at the governor’s mansion in downtown Denver, said the value of getting vaccinated is “simple math.”
“We’re not just advising you to do something that cuts your risk in half or marginally reduces it,” Polis said. “You reduce your risk 10 to 15 times.”

The state had been waiting to release data on the efficacy of vaccine boosters in Colorado until officials could be confident that it was accurate. 

“The challenge is we needed enough hospitalizations to occur, enough cases to occur for us to feel confident that we had a large enough data set to confidently analyze,” Herlihy said. 

In fact, Herlihy said, the vaccine boosters are probably working even better than the data the state has right now suggest. That’s because boosters were first distributed to immunocompromised and older people who are more susceptible to COVID.

Omicron variant detected in wastewater

Herlihy also said Tuesday that the omicron variant was detected in Boulder’s municipal sewage system. 

Boulder County health officials announced last week that they had detected a case of the variant in a person who had recently returned from a trip to South Africa. But Herlihy said it appears there was enough of the variant found in the sewage sample that “we believe it’s likely more than one case.”

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She said “there’s probably some low level of community transmission” of omicron in Boulder County. 

No additional cases of the omicron variant, which was first identified in South Africa, have been confirmed yet in Colorado, however. Polis said, nonetheless, that he is confident there will be more.

Herlihy and Polis also warned Coloradans that coronavirus remains prevalent in the state despite a dip in cases and hospitalizations in recent weeks and cases were back up 

Hospitalizations rose Tuesday and the seven-day average of new daily cases has been higher over the past few days.

“There’s really no clear pattern,” Polis said.