How safe is vaccine? Should pregnant women get it? Your questions answered.

As Advocate Aurora hospitals start to receive precious deliveries of COVID-19 vaccines, the system's infectious disease expert and a nursing leader held a virtual town hall Wednesday to answer questions about the historic vaccination effort.

Dr. Robert Citronberg and Jane Dus, regional chief nursing officer, led the Q&A session. Here is a sampling of their responses.

Q. How safe and effective is the vaccine?

A. Clinical trials show the vaccine developed by Pfizer and the German company BioNTech appears 95% effective. Pfizer did not report any serious safety concerns.

“After looking over all the data that's available, I think that the risks of getting COVID, getting sick from COVID and dying from COVID far outweigh the risks of the vaccine,” Citronberg said.

Some expected side effects may include pain at the injection site, fever, fatigue, headache or chills. Those are signs that the immune system is responding to the vaccine, as intended, and generating antibodies against the spike protein of the coronavirus, Citronberg said.

Q. Why do the leading vaccines require two doses?

A. Pfizer's vaccine is given in two doses, three weeks apart. Federal regulators later this week will likely authorize a second vaccine — this one developed by Moderna and the National Institutes of Health — that also needs two doses, four weeks apart.

“The first doses essentially primes the immune system to make the antibodies, and the second dose enhances that response,” Citronberg said.

You also need to complete the two-dose regimen with the same vaccine. “I would take either one,” Citronberg said.

Q. Who's first in line for the vaccine?

A. The initial doses are reserved for health care workers, and residents and employees of long-term care facilities, per federal guidelines.

Advocate Aurora Health, one of the largest health systems in the Midwest, is prioritizing front-line staff. Advocate Sherman Hospital, Advocate Good Samaritan Hospital, Advocate Good Shepherd Hospital and Advocate Condell Medical Center are set to begin vaccinating employees today.

“Our goal is that the vaccine should be easily available in pharmacies, doctors' offices, hospitals, federally qualified health care centers, but right now we really need to focus on where the priority is, and that's health care workers,” Dus said.

Medical experts expect it will take months before the vaccine is widely available to the general public.

Q. Should pregnant women get the vaccine?

A. Pregnant women were excluded from the vaccine trials, so there's a lack of data available on the safety of the Pfizer-BioNTech vaccine during pregnancy.

Advocate is recommending that employees who are pregnant or planning a pregnancy discuss the potential risks and benefits with their doctor.

“You will not be prohibited from receiving the vaccine, but we want there to be a really good conversation with your doctor to determine if the vaccine is right for you,” Citronberg said.

Q. Should I still get the vaccine if I've already had COVID-19?

A. Yes, but wait at least three months until after your infection has resolved before you roll up your sleeves for the vaccine. The reason mostly has to do with prioritization. The risk of reinfection with COVID seems to be “very low” within the first three months, Citronberg said.

“It's really important to understand that people who had either asymptomatic illness or a mild illness may not generate enough antibodies to provide immunity against future infections,” he said, “so we absolutely want people to get immunized if you've had COVID before.”

Q. How long can I expect the vaccine to protect me from the virus?

A. That's an open question. A couple scenarios: You might need a booster shot after a few years or you might need annual immunization, just like the flu shot.

“We'll know that even probably as soon as next year and give advice,” Citronberg said. “But right now, our primary motivation, all our energy is going to get that primary series in so we can end the pandemic.”

Q. Do I still need to wear a mask after I've been vaccinated?

A. Yes. You could potentially acquire the virus, it could live in your nose and you could spread it to other people, even though you've been immunized and may not fall ill, Citronberg said.

“Until we have more information, we're going to ask everyone to continue masking, continue social distancing, and that will probably continue until we've achieved herd immunity in our population.”