An Anoka County resident who is Minnesota's third case of COVID-19 is hospitalized in critical condition, leaving state epidemiologists without the individual's immediate help to identify close contacts who might also be at risk of infection.

State health officials who announced the finding Tuesday said the priority is the patient's health and recovery. So they are relying at first on information from the patient's relatives to identify and evaluate those contacts, said Kris Ehresmann, infectious disease director for the Minnesota Department of Health.

"Certainly there will be exposures," she said. "But this is another situation where the individual and family took great care to isolate, and that makes all the difference in the world for our work and for the community."

The Anoka County resident appears to have been infected in another state through contact with international travelers, she said. Minnesota's first two cases also were associated with travel — as was a case announced Monday in nearby Pierce County, Wis. That is significant to health officials because it means there is no evidence yet of the virus spreading from person to person in either state.

Ehresmann said Minnesota is still pursuing a containment strategy to prevent or slow the arrival of the corona­virus, which first emerged in China in December. The state consequently has not yet recommended the cancellation of mass events that might be necessary if the virus gains a foothold here.

"When we get to the point where we are seeing multiple cases from multiple different areas, that is when we would start to look at a stronger community mitigation message. … Even as we are focusing on containment, we need to be thinking about the next steps," she said.

Many organizations are taking better-safe-than-sorry precautions, including the Osceola, Wis., school district, which canceled classes Tuesday so that its buildings and buses could be sanitized.

The Pierce County case involved someone who wasn't aware of being infected until after attending a Destination Imagination regional tournament at Osceola High School on Saturday.

Others at the event are considered to have been at low risk of exposure, unless they had prolonged and direct contact with the infected person. The virus also was unlikely to linger on surfaces the patient touched, but school officials took no chances.

"Safety is our No. 1 concern," said Mark Luebker, superintendent for the district in Osceola, which sits along the St. Croix River across from Minnesota.

Wisconsin officials backed the decision and said it complied with guidelines from the U.S. Centers for Disease Control and Prevention for stopping the spread of COVID-19, the respiratory illness caused by this coronavirus.

"This is a new virus, so all the science of how long it can stay on surfaces is still being worked out," said Dr. Ryan Westergaard, chief medical officer for Wisconsin's Bureau of Communicable Diseases.

Minnesota's first two cases involved a Carver County resident in their 50s who had been traveling in Europe and a Ramsey County resident older than 65 who had been on a cruise between California and Mexico.

Both patients are recovering at home under strict isolation procedures.

The Anoka case involves someone in their 30s who felt sick Feb. 28 and sought health care March 3.

Ehresmann said the patient was sent home at that time due to symptoms that did not require hospitalization.

The state's public health lab was in its second day of testing on its own for COVID-19, but the federal testing guidance at that point was still somewhat limited to people with relevant travel histories.

"That was seven days ago," Ehresmann said, "and a lot of things have changed."

The severity of the Anoka patient's illness defied the trend of this global outbreak, which so far has resulted in higher death and complication rates for older people. Ehresmann said she couldn't comment on why the patient is in critical condition.

The patient doesn't appear to have any obvious underlying health problems that could have worsened the infection.

Minnesota's public health lab as of Tuesday morning had tested 135 samples from people at risk for COVID-19.

Gov. Tim Walz on Tuesday signed a $21 million funding bill for COVID-19 preparedness, including continued state testing and contact investigations.

State and federal lawmakers are both debating financial support or tax relief so that people who are sick, or think they might have been exposed to the virus, don't feel financial pressures to go to work when they should stay home.

The incentive to work while sick might be stronger for the 900,000 Minnesotans who lack the employment benefit of paid sick time, said House Majority Leader Ryan Winkler, DFL-Golden Valley. "For purposes of disease management, we have to make sure that we're not undermining our public health by people being forced to come to work."

Senate Majority Leader Paul Gazelka, R-East Gull Lake, acknowledged that self-quarantines for illness or potential exposure could become a "tough situation" for many.

He said while he'll listen to concerns, he doesn't think action on financial assistance or more sick time for such cases is needed at this point.

While as many as 80% of infected people suffer mild symptoms, health officials are concerned because nobody has immunity to this virus and no vaccine exists.

Studies out of China suggest that it can take up to 14 days for symptoms to emerge after infection — hence the length of quarantine orders. Two University of Minnesota students remain under quarantine off campus after they came in contact in Italy with someone who had COVID-19.

University of St. Thomas students recalled from study abroad in Rome have been asked to stay at home for two weeks as well.

Nobody had been in close enough contact with Minnesota's first COVID-19 case to warrant self-quarantines, but a state investigation found as many as 20 people who had been in proximity to the second Carver case and were at some risk.

People at highest risk, such as spouses and other household members of COVID-19 cases, are asked to remain at home for two weeks.

People at medium risk are quarantined as well but can make trips to buy food, medicine and essentials.

Medium risk is defined as someone who spent 10 minutes within 6 feet of an infected person.

People with low risks — such as attendees at the Osceola competition who just happened to be in the same building as a confirmed case — need to monitor their health and report any illness.

While initial studies in China show low rates of infection and complications among children and teenagers, many U.S. schools and universities aren't taking chances.

Harvard University in Cambridge, Mass., said students should move off-campus by Sunday and take online classes for the rest of the semester.

At the University of Minnesota, administrators and faculty at the Duluth, Rochester and Twin Cities campuses are preparing for the possibility of moving to online classes when spring break ends and classes resume next week, though officials haven't officially closed campus yet.

On Tuesday, President Joan Gabel announced that all university-funded international and domestic travel is canceled starting on Monday, after already canceling student programs to Italy, South Korea and China.

The U follows Minnesota State, which indefinitely suspended all international trips for students and faculty at its 37 community colleges and universities.

Wisconsin's COVID-19 cases involved people likely infected during domestic travel.

Spring break travelers need to use "best judgment" about their plans, said Jeanne Ayers, Wisconsin State Health Officer and administrator of the Division of Public Health.

People at greatest risk from COVID-19 should avoid buses, planes and ships — and not travel to states such as Washington and California where the virus is known to be spreading, she said.

The mood in Osceola on Tuesday ranged from glee among students over getting a free day to frustration over the level of precautions.

Aaron Kittelson said his wife, Heather, isn't worried even though she is a teacher who was at the Destination Imagination event.

"She's not worried," he said. "I'm being cautious, washing my hands a lot. Just common sense. … My thoughts are, we're all going to get it eventually."

Staff writers Glenn Howatt, John Reinan, Kelly Smith and Torey Van Oot contributed to this report.