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Advice is evolving along with the coronavirus. Here's the latest from staff and wire reports.

Where can I see Minnesota's COVID-19 numbers?

Check our COVID tracker.

Where can I get a vaccine?

Check the state of Minnesota's vaccine page.

Where can I get tested for COVID-19?

Minnesota has several free COVID-19 testing sites that offer saliva and/or rapid tests, although many will be closing amid declines in testing. Many offer rapid access to antiviral treatment. Health care providers and some pharmacies also offer testing.

Minnesota phased out a mail-in COVID-19 testing program and is now offering free rapid at-home tests. Order your tests here. Free tests also can be ordered from the federal government at covidtests.gov.

You may find home rapid tests at pharmacies including Walgreens and CVS, grocery stores, health care providers and online. Read more about testing here.

Minnesota health insurers are beginning to cover the cost of at-home COVID-19 tests, but state officials advise that consumers should contact health plans first to understand how to access the new benefits. Minnesotans are finding plenty of gaps and footnotes in coverage. Insurers will pay up to $12 per individual test, or $24 for a package that contains two tests, and provide coverage for up to eight tests per person per month. UnitedHealthcare has agreements with Walmart and a growing list of retailers to make available free at-home COVID-19 tests when subscribers present their ID cards at pharmacy counters.

What if my free tests are expired or about to expire?

Federal regulators on June 7 extended the usefulness of the iHealth rapid antigen tests for three months beyond their listed expiration dates, giving Minnesotans more time to use them.

The three-month extension applies only to the iHealth tests with listed expiration dates no later than Sept. 29. Other tests beyond their permitted expiration dates shouldn't be used, because the chemical and molecular components won't be as effective at detecting the coronavirus that causes COVID-19. Read more here.

What should I do if I test negative if I've been exposed?

If you were exposed to COVID-19 and don't have symptoms, take three home tests instead of two to make sure you're not infected if you test negative, according to new U.S. recommendations.

If you have COVID-19 symptoms, test again 48 hours after the first negative test. If you get a negative result on the second test and you are concerned that you could have COVID-19, you may choose to test again 48 hours after the second test, consider getting a laboratory molecular-based test or call your health care provider. Read more here.

What should I do if I've been exposed to the virus?

The CDC said anyone exposed — regardless of vaccination status — should get tested five days later, if possible. It said quarantining at home is not necessary, but urged people to wear a high-quality mask for 10 days. Read more here.

What should I do if I test positive for COVID-19?

The CDC said people who test positive should isolate from others for at least five days, regardless of whether they were vaccinated. If you live with other people, that means staying in a separate room and using a separate bathroom, if possible. You should also wear a mask if you come into contact with others.

You should get care if you have trouble breathing or develop other serious symptoms. But there are many people with certain conditions — including heart diseases, diabetes and weakened immune systems — who should seek care even if they have mild illness, because of their elevated risk for developing serious complications. You should tell your doctor, who may prescribe medications. Tell the people you've been in close contact with.

People with symptoms during isolation, or who develop symptoms during quarantine, are encouraged to stay home.

CDC officials advise that people can end isolation if they are fever-free for 24 hours without the use of medication and they are without symptoms or the symptoms are improving. The CDC said people should wear masks everywhere for the five days after isolation ends.

The CDC cited evidence showing that people with the coronavirus are most infectious in the two days before and three days after symptoms develop.

Can kids who've been exposed to COVID go to school?

The CDC on Aug. 11 ended the recommendation that schools do routine daily testing, although that practice can be reinstated in certain situations during a surge in infections, officials said.

The CDC also dropped a "test-to-stay" recommendation, which said students exposed to COVID-19 could regularly test — instead of quarantining at home — to keep attending school. With no quarantine recommendation anymore, the testing option disappeared too. Read more here.

What about boosters?

The CDC recommends one booster shot for everyone 5 and up. A second booster is reserved for those age 50 and up or those 12 and older who are "moderately or severely immunocompromised." For more information on boosters such as how long to wait after the primary series, go to tinyurl.com/CDCboosterinfo.

Should I wait until new boosters are ready?

Pfizer and BioNTech have new versions of their booster shots that are designed to target the highly infectious omicron family of COVID variants. But multiple vaccine experts said you shouldn't wait. Read more.

U.S. regulators said July 29 they are no longer considering authorizing a second COVID-19 booster shot for all adults under 50 this summer, focusing instead on revamped vaccines for the fall that will target the newest viral subvariants.

How can I make a COVID-19 vaccine appointment for kids in Minnesota?

Minnesota has a webpage (mn.gov/vaxforkids) to help parents and guardians find a vaccine and answer questions.

More than 1,100 Minnesota providers, including pediatricians, pharmacies, local public health agencies and schools, are able to provide vaccines to children. Read more here.

What do federal regulators say about vaccines for kids?

The U.S. on June 18 opened Pfizer and Moderna COVID-19 vaccines to infants, toddlers and preschoolers.

Pfizer's vaccine is for children 6 months to 4 years old. The dose is one-tenth of the adult dose, and three shots are needed. The first two are given three weeks apart, and the last at least two months later.

Moderna's is two shots, each a quarter of its adult dose, given about four weeks apart for kids 6 months through 5 years old.

The FDA also approved a third dose, at least a month after the second shot, for children with immune conditions that make them more vulnerable to serious illness.

The CDC on Nov. 3 cleared kid-size doses of Pfizer's COVID-19 vaccine for children ages 5 to 11. The CDC on June 24 recommended Moderna's vaccines as an option for kids ages 6 to 17.

Read more about vaccines for kids in Minnesota here.

What is the Novavax vaccine?

Novavax shots — already used in Australia, Canada, parts of Europe and dozens of other countries — are a protein vaccine that's made with a more conventional technology than the other U.S. options. The CDC on July 19 endorsed the initial two-dose series for people 18 and older.

Protein vaccines have been used for years to prevent other diseases including hepatitis B and shingles.

Novavax is testing shots updated to better match the newest omicron subtypes — in anticipation of another round of boosters this fall and winter.

What is the omicron variant?

First identified in Botswana and South Africa in November, the omicron variant has surged around the world. Scientists first recognized omicron thanks to its distinctive combination of more than 50 mutations. Some of them were carried by earlier variants such as alpha and beta. Read more here.

Does omicron spread faster than other variants?

Yes. It is two to three times as likely to spread as delta. British researchers found that omicron was 3.2 times as likely to cause a household infection as delta was.

Omicron also appears to have a shorter incubation period than other variants do. People who are infected with omicron typically develop symptoms just three days after infection, on average, compared with four days for delta and five days for earlier variants. Read more here.

What is BA.2? What about BA.2.12.1, BA.4 and BA.5?

There are several genetically distinct versions of omicron. In the U.S. this winter, BA.1 and the highly similar BA.1.1 drove an enormous surge in new cases. In the late winter and early spring, a different subvariant, known as BA.2, gained steam.

BA.2.12.1 s a member of the omicron family, but scientists say it spreads faster than its omicron predecessors, is adept at escaping immunity and might possibly cause more serious disease. That's because it combines properties of omicron and delta, the nation's dominant variant in the middle of last year.

A "delta mutation" appears to allow BA.2.12.1 "to escape pre-existing immunity from vaccination and prior infection, especially if you were infected in the omicron wave," said Dr. Wesley Long, a pathologist at Houston Methodist in Texas.

The genetic change is also present in BA.4 and BA.5, which is now dominant. Those have exactly the same mutation as delta, while BA.2.12.1 has one that's nearly identical.

What is "long COVID" and how many people get it?

Long COVID is the term used to describe an array of symptoms that can last for months or longer after the initial coronavirus infection. Researchers in a large new CDC study identified post-COVID health problems in many different organ systems, including the heart, lungs and kidneys. Other issues involved blood circulation, the musculoskeletal system and the endocrine system; gastrointestinal conditions, neurological problems and psychiatric symptoms were also identified in the study.

One in five adult COVID survivors under age 65 in the U.S. has experienced at least one health condition that could be considered long COVID, according to the study. Among patients 65 and older, the number is even higher: one in four. Read more here.

People with mild or moderate initial coronavirus infections can still experience debilitating post-COVID symptoms. 76% of Americans diagnosed with long COVID were not sick enough to be hospitalized for their initial infection, a new study found. Two-thirds of the patients had preexisting health conditions, but nearly one-third did not. Read more here.

Scientists are racing to pinpoint long COVID's cause. Momentum is building around a few key theories. One is that the infection or remnants of the virus persist past the initial illness, triggering inflammation. Another is that latent viruses in the body, such as the Epstein-Barr virus that causes mononucleosis, are reactivated. A third theory is that autoimmune responses develop after acute COVID-19. Another possibility is that tiny clots play a role.

There is fresh evidence that vaccination may reduce the chances of developing long COVID. Read more here.

What's going on with Johnson & Johnson shots?

U.S. regulators on May 5 strictly limited who can receive Johnson & Johnson's COVID-19 vaccine due to the ongoing risk of rare but serious blood clots. The FDA said the shot should be given only to adults who cannot receive a different vaccine or specifically request J&J's vaccine.

Can I get a vaccine incentive?

The $200 Visa gift card incentive ended Feb. 28. There were drawings for five $100,000 Minnesota college scholarships for all Minnesotans 5-11 years old who are fully vaccinated; the deadline was April 11.

Ramsey County offers a $50 Visa gift card program for people who get their first Pfizer shot at a clinic operated by the St. Paul-Ramsey County Public Health Department, while supplies last. The program is open to everyone, regardless of county residence.

Hennepin County is offering vaccine incentives to community organizations.

How much do vaccines protect against an omicron infection?

During the U.S. omicron wave, two doses were nearly 80% effective against needing a ventilator or dying — and a booster pushed that protection to 94%, the CDC recently reported. Vaccine effectiveness was lowest — 74% — in immune-compromised people, the vast majority of whom hadn't gotten a third dose.

How can I tell if I have a "breakthrough" infection?

Most people will struggle to know for sure based on symptoms alone, without a test to rule out the coronavirus. And if vaccinated people test less often, COVID infections could get dismissed as mild colds or go unnoticed.

British scientist Tim Spector, a founder of the ZOE app that tracks coronavirus symptoms, has said that people thinking they have colds when they really have COVID-19 could help fuel the pandemic. Read more here.

What does the CDC say about masks?

Most Americans live in places where healthy people, including students in schools, can safely take a break from wearing masks under new U.S. guidelines. Read the CDC's latest advice here.

Travelers no longer have to wear face masks at Minneapolis-St. Paul International Airport or while riding Metro Transit trains and buses. A federal judge in Florida threw out a national mask mandate for public transportation across the U.S. The ruling gives airports, mass transit systems, airlines and ride-hailing services the option to keep mask rules or ditch them entirely, resulting in rules that vary by city and mode of transportation.

Americans age 2 and older should wear a well-fitting masks while on public transportation, including in airports and train stations, the CDC recommended May 3, citing the current spread of coronavirus and projections of future COVID-19 trends.

An uptick in COVID-19 activity prompted the city of Minneapolis on April 28 to recommend public indoor mask wearing again.

Should I still wear a mask?

Lab researchers have found that various types of face masks, including cloth masks, surgical masks and N95 respirators, help prevent the spread of the coronavirus. Read more about the science of masking to help you make decisions about if, when and where to cover your face.

Is there a vaccine requirement in Minneapolis and St. Paul and at the U?

Minneapolis and St. Paul jointly rescinded their vaccine-or-test emergency regulations for restaurants, bars and entertainment venues. The University of Minnesota also lifted its requirement. Individual business and outlets may continue requiring them.

What about entertainment venues and restaurants?

Requirements are changing, so it's best to check with a venue.

Audience members have to show proof of full COVID-19 vaccination or negative test results to get into a show at the Dakota, the Cedar Cultural Center and the Uptown VFW aka James Ballentine VFW Post 246. In addition to that requirement, masks are required at the Mixed Blood, Penumbra, as well as select shows at First Avenue and its sister venues and Live Nation's Fillmore and Varsity Theater. Proof of full vaccination plus a mask is required at Walker Art Center screenings and performances.

The Guthrie, Ordway, Minnesota Orchestra, Schubert Club, Park Square Theatre, History Theatre and Hennepin Theatre Trust's Orpheum, State and Pantages dropped the vaccine-or-test requirement, with masks recommended.

Chanhassen Dinner Theatres, the Old Log and Northrop Auditorium have all relaxed their protocols to a degree. Target Center and the Xcel Energy Center have both suspended the requirement that patrons show proof of vaccination or wear masks.

Renegade Theater Company will require proof of full vaccination or a recent negative test to attend its performances at Zeitgeist Teatro Zuccone in Duluth.

The Armory in Minneapolis does not have a standard policy. Attendees are being told to check armorymn.com to find out whether each show has rules in place.

Where do I need to wear a mask?

The CDC recommended that people wear masks in K-12 schools and in counties with high or substantial levels of viral transmission. The Minneapolis and St. Paul districts recently dropped their requirements.

Minneapolis and St. Paul lifted their indoor mask mandates, as have Duluth and Hennepin County. Visitors could still be required to wear masks in correctional, detention and health care buildings.

The state of Minnesota stopped requiring masks in its buildings, although agencies can choose to implement their own policies. Face masks are no longer required to enter Ramsey County buildings. Read more here.

Washington County ended its requirement to wear masks in county buildings Feb. 28, and Dakota County on March 1. There are some exceptions — such as vaccination clinics, jails and courtrooms. Read more here.

Scott County requires masks for all staff outside their offices and for the public at the jail, the courthouse, and public health and mental health centers, said Lezlie Vermillion, county administrator. The county requests the public wear masks in county buildings and will provide them as needed.

Anoka County doesn't required masks in its building except in group settings in the corrections department, a spokesman said.

Masks are required in many health care settings. Some businesses, entertainment venues and employers also may still require masks.

How can I get a quality face mask (and avoid counterfeits)?

There are so many different masks for sale, it's tough to know which ones have been tested and certified by government agencies, and which are counterfeit. Read a guide to choosing the best mask for you here.

Can I get a free N95 mask?

The Biden administration is making 400 million N95 masks available for free to U.S. residents. Read more on finding them here.

What about natural immunity?

A prior infection doesn't seem to offer much protection against an omicron infection although, like with vaccination, it may reduce the chances of severe illness. Health experts say anyone who's survived a bout of COVID-19 still should get vaccinated, because the combination generally offers stronger protection. Read more here.

Is omicron leading us closer to herd immunity against COVID?

Herd immunity is when enough of a population is immune to a virus that it's hard for the germ to spread. Experts say it's not likely that omicron — or any other variant — will lead to herd immunity.

Early hopes faded for several reasons. One is that antibodies developed from available vaccines or previous infection dwindle with time. There's a huge variation in vaccinations. And as long as the virus spreads, it mutates — helping it survive and giving rise to new variants.

Populations are moving toward "herd resistance," where infections will continue, but people have enough protection that future spikes won't be as disruptive to society, said Dr. Don Milton at the University of Maryland School of Public Health. Many scientists believe COVID-19 will eventually become like the flu and cause seasonal outbreaks but not huge surges.

What's going on with the federal vaccine mandate?

The Supreme Court has stopped the Biden administration's requirement that employees at large businesses get a vaccine or test regularly and wear a mask on the job, and the administration has formally withdrawn the rule. But the court is allowing the administration to proceed with a mandate for health care providers that receive federal Medicare or Medicaid funding, affecting 10.4 million workers. The rule has medical and religious exemptions.

The 5th U.S. Circuit Court of Appeals in New Orleans ruled 2-1 on Feb. 9 to maintain a block on a federal worker mandate that a Texas-based federal judge had issued on Jan. 21.

Should you mix or match your COVID-19 vaccine booster shot?

Most Americans should be given the Pfizer or Moderna vaccines instead of the Johnson & Johnson shot that can cause rare but serious blood clots, U.S. health officials said Dec. 16.

How often do COVID vaccines cause heart problems in kids?

While the COVID-19 vaccines made by Pfizer-BioNTech and Moderna do seem to be associated with an increased risk of myocarditis, the latest data indicate that the absolute risk remains very small and that most cases are mild and resolve quickly. Read more here.

Do masks work?

Ordinary surgical and paper masks work when worn properly, said Chris Hogan, a University of Minnesota researcher who has studied mask effectiveness and is editor of the Journal of Aerosol Science.

Generally, the CDC says masks should "fit snugly over your mouth, nose and chin."

If you decide to keep wearing your multi-layer homemade or cloth mask, experts advise washing them every day. But proceed with caution. Read more here.

What about N95s?

Masks are best at keeping your exhaled particles away from others. Respirators, like the N95, also keep others' particles away from you. Any bona fide N95 has been certified to filter at least 95% of particles.

Many doctors and public health experts are now advocating for their use among the general public. Early in the pandemic, people were discouraged the masks over fear there wouldn't be enough for health care workers. That's no longer the case. Read more about N95 and KN95 respirators here.

Are employers mandating the vaccine?

Some workplace policies are making it more of a hassle for workers to resist the vaccine. Others culminate in unvaccinated employees losing their jobs.

Many Minnesota employers were relieved after the U.S. Supreme Court blocked a federal vaccine-or-test requirement. Read more here. But thousands of Minnesota companies now have to decide: With no federal vaccine mandate, should they do it themselves? Read more here.

Bayport-based Andersen Windows and Doors said its existing 6,000 Minnesota workers don't have to be vaccinated, but all new hires do. And to qualify for its newly enhanced 2022 profit-sharing plan, which promises workers up to $4,000 per year, employees must be vaccinated.

Minneapolis-based Graco, with 1,500 Minnesota workers, said it's canceling plans to require vaccines or weekly testing and will terminate all data collection of employees' vaccination statuses. In contrast, the Plymouth candy maker Maud Borup, with 200 workers in Plymouth and Le Center, will continue its vaccine or weekly test mandates.

Many large health care groups such as Allina Health and Mayo Clinic are moving forward with their mandates. On Dec. 8, Maplewood-based 3M told workers that the manufacturer was putting on standby its plans to require vaccination. Read more here.

Macalester, St. Benedict and St. John's, Carleton and St. Olaf said they will require their students and employees to receive a booster dose of the COVID-19 vaccine. Read more here.

Hennepin County requires its nearly 9,000 employees to get vaccinated against COVID-19. Ramsey County requires its 4,000 employees to provide proof of vaccination or submit to regular testing.

In late October, St. Paul Mayor Melvin Carter said nearly every city employee would be required to have their shots completed by the end of the year, with medical and religious exemptions. The union for a wide range of workers joined the police and fire unions seeking a regular testing option. St. Paul postponed enforcement for all city workers after a judge ordered a halt during the litigation. A ruling June 2 said the city cannot institute a vaccine requirement for its employees without negotiating the matter with unions.

A spokesman for Minnetonka-based UnitedHealth Group said a vaccination requirement applies to a "significant portion" of the roughly 220,000 employees in the U.S., including about 18,000 in Minnesota. Workers may request exemptions for medical or religious reasons.

St. Paul Public Schools and Minneapolis Public Schools require employees to be vaccinated or tested weekly beginning Oct. 15. Instead of showing proof upfront, St. Paul staff members will fill out a form and then be subject to potential audits later.

Intermediate School District 287, a cooperative serving about 1,000 high-needs kids in Hennepin County, said it requires staff members to participate in weekly COVID-19 testing or show proof of vaccination.

Minneapolis Mayor Jacob Frey signed an emergency regulation requiring city employees to get vaccinated or get tested regularly.

The Star Tribune required employees who report to work onsite or work with the public to be vaccinated, with an accommodation request process for medical or religious reasons, by Feb. 9.

Minnesota government employees returning to the office must prove they've been vaccinated or comply with at least weekly testing. The mandate applies to roughly 50,000 people who work under the umbrella of state government and on Minnesota State campuses.

Mayo Clinic said workers throughout the Rochester-based health system must get vaccinated or go through an hourlong education session. Essentia Health required all employees to be fully vaccinated by November. With few exceptions for medical and religious reasons, the mandate applies to all 13,000 of the Duluth-based health system's employees in Minnesota, Wisconsin and North Dakota. Sanford Health is requiring all workers to get shots by Nov. 1. The Fairview and Allina health systems announced vaccine requirements with some exceptions for their workers.

The Federal Reserve Bank of Minneapolis said it would require its 1,100 employees to get vaccinated by the end of August. Minneapolis law firm Robins Kaplan also has a vaccine mandate.

The federal Health and Human Services Department is requiring employees who provide care or services for patients to get their shots. The order from Secretary Xavier Becerra will affect more than 25,000 clinicians, researchers, contractors, trainees and volunteers with the National Institutes of Health, the Indian Health Service and the U.S. Public Health Service Commissioned Corps. The VA ordered its health care workers to get vaccinated.

Starbucks is no longer requiring its U.S. workers to be vaccinated.

Walmart required that all workers at its headquarters as well as its managers who travel within the U.S. be vaccinated against COVID-19 by Oct. 4.

Medtronic, which has its operational headquarters in Fridley, said workers need to be vaccinated or have a recent negative test result to enter U.S. offices.

Members of the U.S. military were required to get the COVID-19 vaccine beginning in September, as were employees of the Pentagon.

How does pregnancy affect immunity?

Pregnant women who are vaccinated are nearly twice as likely to get COVID-19 as those who are not pregnant, according to a new study, and have the greatest risk among a dozen medical states, including being an organ transplant recipient and having cancer.

Dr. David R. Little, a researcher at Wisconsin-based Epic, said the findings buttress CDC recommendations that additional precautions against the virus should be taken during pregnancy, such as wearing masks and maintaining safe distances. Read more here.

Should pregnant women get the vaccine?

The CDC urged all pregnant women to get the COVID-19 vaccine as hospitals around the U.S. see disturbing numbers of unvaccinated mothers-to-be seriously ill with the virus. Expectant women run a higher risk of severe illness and pregnancy complications from the coronavirus.

A research study based on data from Bloomington-based HealthPartners and medical centers across the country finds that pregnant women who received COVID-19 vaccines did not experience an increased risk of miscarriage.

If you're thinking of getting pregnant, there's no evidence that any vaccines, including COVID-19 vaccines, influence your chances of getting pregnant despite a myth suggesting otherwise.

Do pregnant women who get vaccinated pass the protection to their babies?

COVID-19 vaccines during pregnancy can protect babies after they're born and lead to fewer hospitalized infants, a new U.S. government study suggested.

What if I'm going to Canada?

Canada will no longer require a pre-arrival COVID-19 test for vaccinated travelers as of April 1. See CDC travel guidelines here.

What about other countries?

After two years of warning travelers to avoid visiting a very long list of countries deemed to be "high risk" for coronavirus infection, the CDC has dropped them all from its list. Read more here.

Are the vaccines approved by the FDA?

The U.S. gave full approval to Pfizer's vaccine on Aug. 23. The formula, jointly developed with Germany's BioNTech, will be marketed under the brand name Comirnaty. The U.S. granted full approval to Moderna's vaccine, Spikevax, on Feb. 7.

Johnson & Johnson, maker of the third option in the U.S., has not yet applied for full approval.

Are the vaccines safe?

A review of 6.2 million vaccine recipients in Minnesota and seven other U.S. regions found no significantly elevated rates of conditions such as stroke or heart attack immediately following COVID-19 vaccination. Bloomington-based HealthPartners participated in the study, which looked for elevated rates of 23 potential side effects in the first three weeks after people received Pfizer or Moderna COVID-19 vaccines.

Who qualifies for an extra shot?

Federal officials approved an extra dose for those undergoing cancer treatment, who've received organ transplants or had other conditions that depress the body's immune system. These doses are not considered to be boosters.

Can kids get long COVID?

Yes, but studies indicate they're less likely than adults to be affected by symptoms.

A recently published U.K. study found about 4% of young children and teens had symptoms more than a month after getting infected. Fatigue, headaches and loss of smell were among the most common complaints and most were gone by two months. Coughing, chest pain and brain fog are among other long-term symptoms sometimes found in kids, and can occur even after mild infections or no initial symptoms.

Some studies have found higher rates of persisting symptoms than in the U.K. study.

Kids can develop other rare problems after a coronavirus infection, including heart inflammation or a condition known as multisystem inflammatory syndrome. Because of the potential for long-term consequences, the American Academy of Pediatrics recommends follow-up doctor visits after children recover from an initial coronavirus infection.

How do Pfizer and Moderna vaccines compare?

In a half-dozen studies, Moderna's vaccine appeared to be more protective over the long term than the Pfizer-BioNTech vaccine.

What is the Docket app?

Minnesota introduced the Docket app for viewing personal immunization records in response to rising demand — largely because of more COVID-19 vaccination requirements by employers and organizations. State leaders said this is not a prelude toward a COVID-19 vaccine passport or government vaccination requirement.

Correction: Previous versions of this story incorrectly described the Ramsey County Deputies’ Federation’s stance on a proposed COVID-19 vaccine mandate for county employees. Previous versions of this story incorrectly stated the Capella Building requires masks.