Minnesota has identified the nation's first-known COVID-19 infection that involves a more contagious Brazilian coronavirus strain.

Genomic sequencing of lab samples from COVID-19 patients identified the Brazil P.1 variant in a Minnesota resident who recently traveled to Brazil, the Minnesota Department of Health reported on Monday.

State Health Commissioner Jan Malcolm said the discovery underscores the need for continued mask-wearing and social-distancing practices to limit transmission of COVID-19, which is spread by a coronavirus known as SARS-CoV-2.

Infections, hospitalizations and deaths from COVID-19 have been declining in Minnesota over the past month, but Malcolm said new strains could contribute to a new wave.

"We know that even as we work hard to defeat COVID-19, the virus continues to evolve as all viruses do," she said. "That's yet another reason why we want to limit COVID-19 transmission — the fewer people who get COVID-19, the fewer opportunities the virus has to evolve."

Gov. Tim Walz mentioned the threat of new viruses on Monday amid a new challenge to hasten the administration of COVID-19 vaccine in the state. Limited doses are currently prioritized for health care workers and long-term care facility residents, but Minnesota recently provided some expanded access to senior citizens and teachers.

Minnesota has launched a variant surveillance program by which its public health lab and others examine 50 random samples from COVID-19 patients each week. The state has conducted similar sequencing throughout the pandemic to chart the spread of the virus — including an outbreak in Minnesota that started when someone brought the virus back from the Sturgis motorcycle rally.

The patient who had traveled to Brazil became sick in the first week of January and had a sample taken on Jan. 9. The person isolated from others after the infection was confirmed. Health officials are now re-interviewing the patient to learn more about recent travel and contacts.

Sequencing also found two more cases of the U.K. variant, known as B.1.1.7, in Minnesota. Both involved Twin Cities residents who had recently traveled to California. The U.S. Centers for Disease Control and Prevention found an additional Minnesotan with the variant who had recently traveled to the Dominican Republic. Eight cases of the U.K. variant have been identified in Minnesota.

"These cases illustrate why it is so important to limit travel during a pandemic as much as possible," said Dr. Ruth Lynfield, state epidemiologist.

While both variants are more infectious, health officials remain uncertain whether they cause more severe COVID-19 illness.

Jeremy Olson • 612-673-7744