By Raetta Holdman

(CBS4) – The number of new diagnosed COVID-19 has dropped across the naton, including here in Colorado. CBS4 Medical Editor Dr. Dave Hnida said there are a number of reasons for the decrease in an interview on CBSN Denver.

“First and foremost, we are starting to vaccinate people and that is certainly very helpful,” he said.

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“The second thing has to do with behaviors. People’s behaviors are just really consistent. I think people are getting used to things such as masking and social distancing. It’s really the norm these days.”

Hnida also pointed out we have not had much holiday travel recently.

But the most interesting reason may be Hnida’s third point: seasonality.

“We know viruses tend to react to things like temperature, humidity, even the amount of sunlight during the course of the day.”

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“We’re thinking COVID actually may have some sort of seasonality response. It may actually begin to decrease as we head towards spring. We’ll see if that continues to be the case.”

Hnida also said part of the decrease outside of Colorado has to do with the continued lack of testing, pointing out in many places it is still hard to get a test.

“With the number of tests going down we’re not picking up as many cases of COVID as we otherwise might.”

And finally, he said the number of people who have already been infected means the virus has fewer people to infect, even if some people are getting COVID a second time.

“At this point in time, we know we’ve had at least 30 million Americans diagnosed with COVID, we actually think the number of cases is probably triple that because not everybody gets tested.”

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“Overall, thenews is very, very good. We know that the vaccine is effective. We know that the vaccine is safe. We are seeing behaviors and other factors come into this. It’s not time to let our guard down. If we just just the course, we are going to see some brighter days ahead. I’m very optimstic.”

Raetta Holdman