(CN) — Officials from the Centers for Disease Control and Prevention urged Americans on Wednesday to step up social distancing and other measures to curb the spread of Covid-19, a day after confirming a more contagious strain of the virus had reached the United States.
The CDC also confirmed another variant of the coronavirus originating from South Africa is turning up in other countries and may soon appear in the U.S.
“Both of these variants appear to infect people more easily,” said Dr. Henry Walke, the CDC’s Covid-19 incident manager, in a press call. “There is no evidence that either of these variants causes more severe disease or increases the risk of death.”
But an increased number of cases caused by these more contagious versions of the coronavirus could “put even more strain on our heavily burdened health care systems,” Walke warned.
On Tuesday, the Colorado State Laboratory announced a man tested positive for a new coronavirus strain emanating from the United Kingdom. The man, a Colorado National Guardsman, has not traveled recently, indicating the strain is circulating between people in the U.S.
“There is a lot we don’t know about this new Covid-19 variant, but scientists in the United Kingdom are warning the world that it is significantly more contagious,” Colorado Governor Jared Polis said in a statement.
Since then, Colorado health officials say another guardsman may have contracted the coronavirus variant, known as B.1.1.7. Both men were working in a nursing home dealing with a Covid-19 outbreak.
Dr. Greg Armstrong, director of the CDC’s Office of Advanced Molecular Detection, told reporters other states have coronavirus samples that may match the mutation, including California and Massachusetts. The CDC is working with a national laboratory to test samples from around the country to gauge how prevalent the strain is.
“We anticipate getting some data back from that in the next couple of days,” Armstrong said.
“There are lots of laboratories that have this capacity around the U.S. and we’ve heard anecdotally and directly that a lot of them are looking for this variant right now,” he added.
Walke said the CDC’s experts believe the current vaccines will be effective on these coronavirus strains. But he admitted health officials do not know how the variants will respond to drugs and other Covid-19 treatments of those infected.
CDC officials also responded to criticisms that the vaccines are not being dispensed as quickly as previously assured.
On Dec. 1, a CDC panel estimated 20 million vaccines would be available by the end of the month. Yet, as of Wednesday, only 12.4 million doses were distributed with just 2.5 million people receiving the first shot, according to the CDC.
One of the most vocal critics of the vaccine rollout has been President-elect Joe Biden.
“The Trump administration plan to distribute vaccines is falling behind — far behind,” Biden said on Tuesday from his transition team headquarters in Delaware.
“If vaccinations continue at this pace, it will take years, not months, to vaccinate the American people,” Biden added.
Dr. Nancy Messonnier, director of the National Center for Immunization and Respiratory Diseases, which is part of the CDC, recognized the gap in the distribution and administration of the vaccines.
When setting up a vaccination clinic or entering a long-term care facility, she said, health officials want to be sure there is enough doses for everyone.
“So, the process does involve making sure that the vaccine is fully available before launching,” she said.
Still, Messonnier defended the “largest vaccine rollout in the country’s history.”
“It’s important to remember it’s been less than a year since we found out about this virus, and just 20 days ago, that the first vaccine was authorized for use,” she said. “I really expect those numbers are going to increase fast next week.”
More than 19.6 million Americans have contracted the coronavirus over the last eight months, according to Johns Hopkins University. Nearly 341,000 have died from the respiratory disease.