State health officials are stepping up efforts to track whether a variant of the pandemic coronavirus that quickly spread across the United Kingdom is now moving through Minnesota.
Two weeks after the Department of Health reported the state's first cases of the variant, health officials are expanding the genetic sequencing work that scientists perform to document the new strain.
So far, the search in Minnesota hasn't uncovered additional variant infections, but the results provide little comfort. That's because the U.S., in general, has fallen far short of other countries in the lab work needed to track variants of SARS-CoV-2, the virus that causes COVID-19 illnesses.
"The absence of evidence is not evidence of absence," said Michael Osterholm, director of the Center for Infectious Disease Research and Policy at the University of Minnesota. "Our situation right now with genetic sequencing in this country is so unfortunate."
The lack of sequencing work is part of a broader funding problem for public health in the U.S., but there's still a chance for improvement, said Dr. Sallie Permar, chair of the Department of Pediatrics at Weill Cornell Medicine in New York. In the meantime, the threat from the variant can be controlled, Permar said, if people "double-down, triple-down, quadruple-down" on the standard recommendations about social distancing, wearing masks and adhering to quarantine/isolation protocols.
She added that viral variants are setting up a race against time that brings "extreme urgency" to the rollout of coronavirus vaccines.
"The virus is figuring out a way to mutate around immunity, while we're trying to get everyone immune," said Permar, who specializes in immunology. "I believe we can win the race, but it's not going to come without sustained effort over the next few months."
On Saturday, the Health Department reported 31 more deaths from COVID-19 complications and 1,565 new cases. The infections pushed the seven-day rolling average for new cases up slightly to about 1,252, according to the Star Tribune's coronavirus tracker.
The latest data release showed a one-day increase of 15,113 people who have received at least one vaccine dose, for a total of 229,163 people. That's about 4% of the state's population — up from 3% last Saturday, according to Star Tribune estimates.
The coronavirus variant B117 was first found in the United Kingdom in September and is thought to spread more easily than other strains. While health officials have stressed that it does not seem to cause more serious illness among those who are infected, British officials announced last week new evidence that it might actually bring a higher mortality rate, although they stressed uncertainty over the data.
Studies continue to indicate that the COVID-19 vaccines are effective against the U.K. variant.
Minnesota's first cases — five in all — came as 63 cases were reported across eight other states. In two weeks, the tally grew to 195 cases across 22 states, according to Friday figures from the Centers for Disease Control and Prevention.
Minnesota plans to send more samples for testing to the CDC, said Sara Vetter, interim assistant director of the state public health lab in St. Paul. The state's own lab has been sequencing between 50 and 90 samples per week and hopes to double that number.
"We have increased our capacity to do whole genome sequencing in the public health laboratory and will continue to test positive specimens," Dr. Ruth Lynfield, state epidemiologist, wrote in an e-mail. "We think there are more cases in Minnesota that we have not identified."
Three of the five Minnesota cases found thus far were not linked to travel, which suggests the virus is spreading in the community, the Health Department says. The lack of additional cases suggests the variant is circulating at a "relatively low level," a spokesman said via e-mail.
Genetic sequencing is a laboratory technique to determine the genetic code of a virus — the unique pattern of nucleotides that identify a virus, much like a fingerprint identifies a person, said Dr. Joseph Yao, a specialist in infectious disease testing at the Mayo Clinic. As viruses circulate, mutations occur within the genetic code that can be identified by sequencing.
The process takes time. Whereas running a test to confirm a case of SARS-CoV-2 can take as little as 30 minutes, Yao said, sequencing the genetic code takes at least two days.
In the hunt for variants, health officials don't need to sequence every positive test result, but they should develop a surveillance strategy that regularly analyzes a subset, said Dr. David Boulware, an infectious disease specialist at the University of Minnesota. The United Kingdom has a much more robust surveillance program for variants, Boulware said, so it makes sense the variant was found in southeast England.
The U.S., by contrast, does genetic epidemiology on just one-tenth the scale of the U.K., said William Hanage, an associate professor of epidemiology at the Harvard T.H. Chan School of Public Health.
"It means that there could be some nasty surprises circulating among us that we don't know about yet," Hanage said during a call with reporters last week. "And we should be prepared to see them, if we start looking harder."
The variant's rise, he said, means more people will need to be vaccinated in order to reach the critical vaccine threshold to control the virus.
Variants also have surfaced in South Africa and Brazil, Osterholm said, and others could be coming. He noted the U.K. variant circulated quietly in England for many weeks before surging. It all makes Osterholm fear that the worst of the pandemic is yet to come.
"What we could be facing is the perfect storm of these variants," he said. "You're seeing more data out of Europe, more countries are reporting major increases in transmission. … You saw the data in England, saying maybe they are creating more severe illness. That's why, at this point, I'm very concerned that these are going to take off in the United States ...
"If the variant takes off and causes a big increase in cases," Osterholm added, "it will have a lot of human wood to burn — meaning us."
Staff writer Joe Carlson contributed to this report.
Christopher Snowbeck • 612-673-4744