By Jennifer McRae

AURORA, Colo. (CBS4)– A second coronavirus vaccine in the U.S., that was tested on Colorado volunteers, is proving to be highly effective in the trials. Moderna said its vaccine appears to be 94.5% effective according to preliminary data from the company.

Michael Rouse, 66, of Central Park, is taking part in the Moderna study for the coronavirus vaccine.

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So far, he has received two shots of what he believes were the vaccine and not a placebo. Rouse said that he has had reactions that lasted 12 hours after the first shot and 24 hours after the second.

“Full body aches, muscle aches, chills, nausea, headache and a little bit of diarrhea,” said Rouse. “And after that, I’ve been feeling great.”

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UCHealth is one of 89 research sites across America that participated in phase three study trials of the Moderna vaccine.

(Photo by Emin Sansar/Anadolu Agency via Getty Images)

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It was just last week when competitor Pfizer Inc. announced its own COVID-19 vaccine that boasted a 90% effective rate. Both vaccines require people to receive two shots several weeks apart.

The results are “truly striking,” said Dr. Anthony Fauci, the U.S. government’s top infectious diseases expert, who earlier this year said he would be happy with a COVID-19 vaccine that was 60% effective.

CBS4 Medical Editor Dr. Dave Hnida called the report really good news. “I think the light at the end of the tunnel just got a little bit brighter this week. Once again, accepting the fact this is really early information we are getting.”

“We, for example, don’t know how long it is going to last but it does look like it is safe. The fact is, we as Americans now have something to look forward to. We’ve just got to hang on as we go down this stretch.”

If the FDA approves emergency use of Moderna’s or Pfizer’s vaccine there is expected to be limited supplies before the end of the year. Those considered high risk will be among the first to receive the vaccine.

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Gov. Jared Polis has stated previously that the vaccine would be distributed in three phases in Colorado with those in the high risk category receiving the vaccine first, followed by the population that falls into the other two phases. Last week, Polis said that that goal is to have enough doses so that everyone in Colorado can be vaccinated if they choose, by late spring 2021.

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One of the challenges is that both Moderna and Pfizer vaccines are frozen but at different temperatures. Moderna’s vaccine can last longer in a refrigerator than initially thought once thawed, up to 30 days. Pfizer’s vaccine requires long-term storage at below zero temperatures.

Jennifer McRae