Fully vaccinated Minnesotans should not try to get COVID-19 booster shots right now, despite media reports that federal officials will approve them soon, state health leaders said Tuesday.

Federal officials have not released any details about when booster shots would begin or eligibility criteria, but federal officials may release some information Wednesday. Minnesota health officials said they have not been notified about a booster program.

Even if boosters become recommended, they most likely will be given first to health care workers and long-term care residents, the same groups that were designated as high priority when the shots started going into arms in late December. For now, Minnesota's top health official said the priority should be those who are not fully vaccinated as well as people with weakened immune systems who last Friday became eligible for a third dose.

"We would really put a plea out to Minnesotans to … really respect the fact that there are priorities here," Minnesota Health Commissioner Jan Malcolm said.

White House COVID-19 adviser Dr. Anthony Fauci and National Institutes of Health director Dr. Francis Collins both recently said that boosters would probably be needed because some studies indicate that COVID-19 immunity wanes over time.

While the vaccines are still considered effective at preventing serious illness and hospitalizations, a study from the Mayo Clinic last week noted that the effectiveness of the Pfizer and Moderna vaccines declined over the summer. The Johnson & Johnson vaccine was not part of the research.

The concern is that even mild or asymptomatic infections in fully vaccinated people could create a chain reaction of infections in others, especially high-risk populations, because of the highly infectious delta variant, which is now dominant across the country.

Federal health officials reportedly are considering that boosters be given eight months after the second dose.

Last week, federal officials approved a third 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, which are designed to address waning immunity, because immunocompromised people typically did not develop a good immune response from the initial doses.

But when the Centers for Disease Control and Prevention made the recommendation, it said that people would not be required to prove that they had weakened immune systems, saying it would be based on the honor system.

While health care clinics know the medical histories of their patients, most pharmacies don't have detailed records apart from prescriptions filled, creating a back door for people who are not eligible to get a booster.

The CDC estimates that 1.1 million U.S. residents have already gotten a booster since vaccinations began. Data for Minnesota residents was not immediately available.

Getting a booster too early could be unnecessary because COVID-19 immunity is still high. "We want to make sure that we are taking full advantage of the immunity that the two doses provide people," state infectious disease director Kris Ehresmann said.

Minnesota health officials have not received any details about the timing of an announcement about boosters or who would be eligible.

Ehresmann said the 500,000 health care workers and long-term care residents who got the first initial doses would be first in line to get boosters as their immunity would be the most likely to be providing less protection.

Minnesotans should not be concerned about getting boosters soon in fear that the vaccine supply will tighten.

"Once a booster is recommended likely not everyone in Minnesota will be needing to get a booster at the same time," she said. "So there will be time and there will be plenty of vaccine available."

Nearly 2.8 million Minnesotans have received two doses of the Moderna and Pfizer vaccines. About 274,000 have received the one-dose Johnson & Johnson shot, which is not believed to be part of the initial announcement about boosters.

Pharmacists said they are starting to field more questions about booster doses, but that the greater volume of calls is from COVID-19 vaccine holdouts.

Some callers to Casey Drug in Chisholm want to take advantage of new company incentives while others plan to travel to Canada now that the borders are open to vaccinated individuals. Others assume their employers will require vaccinations after the U.S. Food and Drug Administration gives full approval to the first COVID-19 vaccine made by Pfizer.

"On one hand, many people know their employers will mandate when Pfizer gets full approval," said Alida Casey, a pharmacist at Casey Drug. "But there also seems to be a good chunk of people who wanted to wait it out until the vaccines were around longer, and they see now that COVID is definitely coming back this fall."

Last week's announcement about third doses for the immunocompromised has created confusion.

"I think what has a lot of people confused is that the boosters we are doing now are specifically for people who did not get a good immune response … as opposed to people who are higher risk" from other medical conditions, she said.

Some parents with vaccine concerns are consenting to get shots for their teens out of concern that they could otherwise miss in-person learning or school sports this fall.

Free COVID-19 testing kits will be offered to schools as will grant money to help with supplies and staffing support, the state's health and education departments said Tuesday.

Unvaccinated students and staff should get tested weekly and students who participate in school sports should get tested more often, according to recommendations. Vaccinated people should get tested if they feel sick or are exposed to a COVID-19 case.

Minnesota has confirmed 629,354 COVID-19 cases after 3,054 new cases were announced Tuesday. That total reflects three days of results for an average of about 1,000 cases per day.

Another three deaths were reported, bringing the pandemic total to 7,737 fatalities.

Staff writer Jeremy Olson contributed to this report.