Four weeks after Gov. Tim Walz ended Minnesota's mask mandate for indoor public places, pandemic activity has dropped to record lows in the state — with 175 coronavirus infections reported Thursday and seven COVID-19 deaths.

The additions bring Minnesota's totals in the pandemic to 603,305 known infections and 7,484 COVID-19 deaths but underscore how vaccination progress has reduced viral activity even with removal of the mandate and social distancing restrictions.

Thursday is the fourth straight day in which the state reported fewer than 200 infections — the first such stretch since April 2020.

"We are in a good place with our pandemic numbers," state infectious disease director Kris Ehresmann said. "For the first time, we are 'in the green' with some of our metrics."

New infection and COVID-19 hospitalization rates dropped below Minnesota's caution thresholds this week for the first time since the start of the pandemic — with the 2.2% positivity rate of COVID-19 testing already below the state's 5% caution level.

Public health officials throughout the pandemic have looked at infection numbers four weeks after major changes in restrictions or strategies because of the lag in which those changes affect viral transmission.

In addition to the end of the mask mandate on May 14, the state lifted all capacity caps and social distancing requirements on businesses on May 28.

Vaccination is the primary prevention strategy now in Minnesota, where nearly 3 million people 12 and older have received at least a first shot of COVID-19 vaccine and nearly 2.7 million have completed the one- or two-dose series.

Progress toward a state goal of providing vaccine to 70% of people 16 and older by July 1 has slowed. The rate in that age group now is 65.5%.

Walz on Wednesday announced the opening of a second airport pop-up vaccination site — this time at Terminal 2 of the Minneapolis-St. Paul International Airport — to make it easy for people to receive their shots.

"You can now protect yourself from COVID-19 in one stop while you catch your flight, or wait for your loved one to land," Walz said in a statement about the clinic, which is outside of the secured areas of Terminal 2.

Health officials believe a vaccination rate of 70% or higher will limit spread of the SARS-CoV-2 coronavirus that causes COVID-19 and reduce the formation of infectious variants that could fuel a new pandemic wave.

The state on Thursday reported that 90% of senior citizens have received vaccine — a high-risk group that has suffered 88% of Minnesota's COVID-19 deaths and six of the deaths reported Thursday. The seventh death involved a Roseau County resident in the 35 to 39 age range — only the 65th COVID-19 death in the state involving someone younger than 40.

The rising count of variant infections raises concerns, Ehresmann said, because more Minnesotans are getting variant infections in the state rather than traveling to other countries and getting infected with variant strains elsewhere.

While genomic sequencing is conducted for only a handful of positive tests, an estimated 80% of new infections in Minnesota are linked to more infectious variants — particularly the B.1.1.7 variant identified in England.

The state has identified 43 infections involving the B.1.617.2 variant that fueled a widespread outbreak in India. Nearly one-fourth of identified infections with that variant resulted in hospitalizations for COVID-19 illness.

Hospitalization rates also have been elevated among the 360 infections involving the P.1 variant identified in Brazil and the 225 infections involving the B.1.351 variant identified in South Africa.

"For this reason," Ehresmann said, "the push to get all Minnesotans vaccinated remains."

Jeremy Olson • 612-673-7744