Federal agencies have approved updated COVID-19 vaccines and they could be available this week for everyone 6 months or older.

The Food and Drug Administration approved updated formulations of the Pfizer and Moderna vaccines on Monday. And an advisory committee for the U.S. Centers for Disease Control and Prevention gave its key approval on Tuesday.

“Let’s keep America strong, healthy,” Dr. Camille Kotton, a member of the U.S. CDC’s advisory panel, said during the advisory committee’s meeting Tuesday. “Let’s do away with COVID-19 as best we can by prevention of disease through vaccines.”

CDC Director Dr. Mandy Cohen quickly signed off on the recommendations, the final official step in the process. “CDC is now recommending updated COVID-19 vaccination for everyone 6 months and older to better protect you and your loved ones,” Cohen said in a prepared statement.

The Maine Center for Disease Control and Prevention did not respond to questions Tuesday about rollout of the new vaccines, saying that the agency will have more information later this week.

The new round of COVID-19 vaccines comes nearly three years after the first immunizations became widely available in January 2021, and some people have received four or more COVID-19 shots since the pandemic began.

And it comes as case counts have increased in Maine and nationwide in recent weeks, and as children and college students are returning to classrooms, where the virus can spread more easily. Wastewater testing also is showing much higher coronavirus concentrations in most Maine counties, including a large spike in Cumberland County in August. The presence in wastewater is a real-time indicator that virus prevalence is rising.

While the updated shot will be available soon, when should you roll up your sleeve? And should you get an influenza shot at the same time? Here are the latest answers from public health experts.

How soon can we get the new vaccine in Maine?

The federal regulatory actions set the wheels in motion for the vaccines to be delivered to pharmacies and health care providers across the nation this week.

Exactly when the vaccines will arrive in Maine is uncertain, but the initial shipments should be within days. Based on past rollouts, it can take a week or more to get appointments.

When should I get the new COVID-19 vaccine?

“I would recommend getting it as soon as you can since there is an uptick in COVID-19 cases,” said Dr. Dora Anne Mills, chief health improvement officer for MaineHealth, the state’s largest provider network. “Our immunity is waning, and these vaccines will boost our immunity. Our basic options are to get infected and risk serious illness and pass the virus to others, or get vaccinated.”

Those who got the most recent booster shot last fall likely no longer have immunity from those shots, experts say.

What if I just had COVID?

People who had a recent COVID-19 infection and do not have underlying health conditions can have natural immunity for several months before the protection fades, the U.S. CDC says. However, people with weakened immune systems who get an infection may have a limited immune response or none at all, the agency says.

Do the new vaccines protect against the latest variants?

The updated vaccine is formulated for the latest subvariant of the omicron strain, XBB.1.5. While new variants continue to emerge, the vaccines approved this week are generally expected to offer protection against all circulating strains. Vaccines reduce the chance of an infection and reduce the odds that any infection causes severe illness.

Mills compared the new COVID-19 vaccines to the annual influenza shot, which is given every fall as the best tool to ward off infection and illness.

For the flu shot, scientists try to predict what strains will be circulating months in advance of the winter flu season. Mills expects a similar strategy for COVID-19 every year, with scientists working on formulations to match the most widely circulating strains.

Does that mean COVID-19 is similar to influenza?

While the public health response to COVID-19 now more closely resembles the approach to seasonal influenza – and both are respiratory diseases caused by viruses – COVID-19 remains far more dangerous.

“COVID-19 is about four times deadlier than influenza,” Mills said. “The coronavirus continues to circulate and evolve.”

But Mills said the ways people can protect themselves from respiratory illnesses like COVID-19 and influenza are similar. Get vaccinated, wash hands frequently, stay home when sick and wear a mask around others if you are in a high-risk group.

“This is all about being prepared for the season of respiratory illnesses,” Mills said. Those 60 and older and pregnant women also are eligible for the RSV vaccine being rolled out this fall. RSV is another common respiratory illness that can be dangerous for infants and older people.

Should I get my COVID-19 shot and flu shot at the same appointment?

Mills and other public health experts say you can get both during the same appointment, and many primary care practices are scheduling both shots during the same session. The RSV vaccine would typically be given during a different appointment.

However, Mills said people can wait until later in the fall to get the flu shot, but should get the COVID-19 shot as soon as possible. That’s because while COVID-19 is circulating widely now, influenza sometimes doesn’t show up as frequently in early fall, and there can be surges of influenza in March and April. Mills said people who get their flu shots in August or early September may experience waning immunity by March.

Does my insurance cover the COVID-19 shot?

Yes. Private insurance plans, Medicare and MaineCare cover vaccines, so in most cases the vaccines should be free to patients, especially if you go to an in-network health care provider. For the uninsured, community health clinics will likely offer free vaccines this fall, public health experts said.

The total cost of the updated vaccines are slightly more than $100 per dose, but for the most part patients will not be not paying to receive the vaccines.

Where will I be able to get the COVID-19 vaccine?

It will be widely available, at major pharmacies such as Walgreens, CVS and Walmart, and at health care providers, such as primary care practices.