Colorado is shattering daily records for COVID-19 infections while hospitalizations have soared to the highest levels since the worst peaks of the pandemic, prompting stern pleas from Colorado’s governor and medical experts urging people to wear masks and sharply limit social interactions.

Gov. Jared Polis stopped just short of issuing stay-at-home orders, but called on Coloradans to “save the life of a stranger” and immediately halt all in-person social gatherings with people outside of their homes during the month of November.

Several Colorado counties also are limiting public activities. Denver and nearby counties have imposed curfews, and if the fall spike in COVID-19 cases in Colorado continues to worsen, lockdowns and closures of non-essential businesses could follow.

The startling truth is that the virus that causes COVID-19 is so widespread throughout Colorado that it’s much easier to get infected now, and in turn, to spread the virus to others. Up to half of people who test positive for COVID-19 have no symptoms.

“The virus is far more dangerous now than in the summer. People are exhausted so they’re hanging out with neighbors and friends,” said Dr. Richard Zane, executive director of emergency services at UCHeath University of Colorado Hospital, and UCHealth’s Chief Innovation Officer.

Zane echoed Polis’ call to sacrifice now in order to save lives in the coming weeks and months.

“We are seeing people of all ages who are coming in critically ill,” Zane said. “People are so tired of the pandemic. I absolutely commiserate with them, but if the social gatherings continue, they are going to kill someone and people don’t want to do that. If we can just rein it in, we can save lives.”

Zane urged people to focus intently on the safety measures that we all know and understand by now.

“The basic blocking and tackling works. Mask-wearing, hand washing and social distancing help reduce cases,” said Zane who is also a professor and chair of Emergency Medicine at the University of Colorado School of Medicine on the Anschutz Medical Campus.

Why did the fall Colorado COVID-19 spike get so serious so quickly?

So, why have infections risen so quickly this fall? Simple. The virus is acting as viruses do. They’re opportunistic and spread easily from host to host, in this case person to person.

“It’s just math. It’s not personal or cultural. It’s pure and simple math,” Zane said. “It’s very different than it was in July.”

State officials now estimate that about 1 out of every 100 people in the Denver area now has COVID-19. That’s a larger ratio than just a few days ago when the estimate was about 1 in 145 people.

“It’s pure probability. As the prevalence of infections in the community goes up, and people spend more time with one another, exposures go up,” Zane said.

Across the U.S. now, more than 10.1 million people have contracted COVID-19. In Colorado, more than 3,000 people are testing positive for the virus each day, the highest number of infections ever recorded during the pandemic and up from just over 100 cases per day at the low point in Colorado in June.

The number of people who are hospitalized in Colorado with COVID-19 also has spiked, jumping from low points of just over 200 at all Colorado hospitals in early September to nearly 1,200 people now. At UCHealth’s 12 hospitals, the number of patients with confirmed or suspected COVID-19 infections has shot up from a low of 33 in September to 262 as of Nov. 10.

Meanwhile, the percent of people who are testing positive for COVID-19 now hovers close to 13%, a dramatic increase from just over 2% in early September. Higher positivity rates indicate that COVID-19 infections are far more widespread now throughout Colorado than they were in the past, meaning that it’s much easier to get infected as people go about their normal activities.

Those rapidly increasing infection rates explain why the governor, health officials and medical experts all are calling on Coloradans to cut down their social interactions. If you spend concentrated time in close proximity with fewer people, you are much less likely to get infected.

During the first wave of coronavirus infections in the spring, Coloradans complied with stay-at-home orders, businesses closed and everyone “flattened the curve,” meaning that by staying in our homes and apart from one another, we drove down exponential growth in infections.

Over the summer, many more people wore masks and gathered outdoors where the virus doesn’t spread as easily.

The virus seems to thrive in cool, dry air and social gatherings are spreading it

Dr. Rachel Herlihy, Colorado’s state epidemiologist, also said that evidence is mounting that the virus spreads better in cold, dry environments, exactly the weather that we are having now. The COVID-19 outbreak is perfectly mimicking the 1918 flu pandemic when cases started in the spring, eased in the summer and rose again in the fall.

Zane said high infection rates at colleges and universities certainly triggered some Colorado spikes late in August and early in September, but he doesn’t think schools are to blame for the current spikes. Children and teachers in K-12 settings (for those who are having in-person classes) are being very compliant with public health guidelines by wearing masks and practicing social distancing.

“They’re getting COVID-19 outside of schools at small, multifamily gatherings,” Zane said. “I think the college kids have been locked down. They were problematic as a whole group, but the biggest problems is regular folks are having multi-family gatherings.”

We’ve all gotten too relaxed in social settings, Zane said.

Adults and young people alike yearn for company, so people are dining out together or hosting parties where too many people are attending and those in attendance are not being careful, staying outdoors and wearing masks.

When we relax now, there’s a higher risk of getting infected because the virus is simply so much more common in the community.

“Now the prevalence is high. It’s just math,” Zane said. “In the summer, the prevalence was low. It’s high now.”

Who is getting hospitalized now during fall Colorado COVID-19 spike?

With COVID-19 hospitalizations reaching spring peaks again, people of all ages are getting critically ill and needing hospital care. In the spring, older adults were most at risk, but Zane said that many older adults remain afraid of the virus and wisely are essentially quarantining themselves.

Young people, on the other hand, have been hanging out together, getting infected and some have needed to be hospitalized.

About 15-to-20% of people with COVID-19 who need hospital care at UCHealth and elsewhere around the state now are people ages 20 to 39. Fortunately, many of these younger patients recover more quickly and have shorter hospital stays than older patients.

In addition to young people, Zane and his colleagues are seeing people between the ages of 40 and 65 who also are becoming critically ill with COVID-19.

“We’re seeing all age groups coming in,” he said.

And while survival rates are improving because doctors now have some experimental therapies and more experience treating COVID-19, there still is no cure. Zane said that if people outside hospitals could see the tragedies unfolding in ICUs, they would be much more careful.

“When people are critically ill and dying of COVID-19, it’s like you’re drowning in Elmer’s glue. The lungs fill up with goop. You can’t get oxygen. And the body shuts down. Organs fail. The kidneys and lungs fail. Every molecule shuts down. It’s a horrible way to die,” he said.

Preventing these unnecessary deaths is absolutely paramount.

Be very wary of quick COVID-19 tests

So, in addition to urging people to halt social gatherings, wear masks and keep distance from one another, Zane also is warning people to be very careful about quick COVID-19 tests, which also are known as rapid antigen tests. People can pop into urgent care facilities, get the tests and get results within 15 minutes. But, Zane said, the results are often wrong.

UCHealth facilities do not offer these tests because Zane and other experts worry that they are not accurate enough. If people get a negative test result, they assume they are healthy. But, in fact, the tests can lead to many false negatives, and that can be dangerous.

Zane said he is hearing about large groups of friends and relatives who want to gather in Colorado resorts, like ski area towns. They plan to fly to Colorado, meet at urgent care facilities, take quick COVID-19 tests, then gather with one another.

Zane said this is not safe.

“Lay people believe test results are accurate. But, this is not a great test. And there are some garbage tests out there,” Zane said.

Ironically, as the underlying prevalence of COVID-19 rises in the community, the sensitivity of the tests also changes, meaning that they are even less reliable now.

“We are now at the point where there’s a higher chance of a false negative than a true negative result,” Zane said.

“If we make important decisions based on unreliable tests, then individuals could hurt other people. People are getting negative test results and feeling that they are safe,” he said.

In fact, people should not make any important decisions based on test results. More important than anything is to change behavior now and to stop socializing.

Like nearly all medical experts, Zane is changing his own plans. His son wanted to have friends spend the night on Halloween. Zane allowed them only to stay in separate tents in the yard.

And, he’s putting the kibosh on holiday gatherings.

“I canceled my Thanksgiving,” he said. “Usually we have people come, but it’s not the right time and place.”

If Coloradans change their behavior now, they can stay healthy and save lives.

“If you keep yourself in a safe place, then it’s still safe.”