By Dr. Mallika Marshall

BOSTON (CBS) – Dr. Mallika Marshall is answering your coronavirus vaccine-related medical questions. If you have a question for Dr. Mallika, email her or message her on Facebook or Twitter.

Dr. Mallika is offering her best advice, but as always, consult your personal doctor before making any decisions about your personal health.

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What has been going through your mind as shipments of vaccine have been arriving at medical centers all over the country?

I’ve been really emotional the past couple of days. Watching the trucks pull out of the Pfizer facility and seeing the staff at hospitals across the country open the boxes to reveal the precious vials, watching the first Americans outside of a trial anxiously receive the vaccine. And to think of the hope this highly safe and effective vaccine brings as record numbers of Americans are dying every day. It brings tears to my eyes.

The first wave of vaccinations to front line health care workers is happening this week. Why is this so important to have them vaccinated first?

It’s important to get these people vaccinated first so that they don’t get sick and put the entire health care system in jeopardy as we enter the toughest period of this pandemic. We’re seeing more and more people in health care settings get infected and have to leave work because they’re sick or they need to quarantine, which makes it harder for us to take care of patients.

First responders, inmates and correctional workers, and long term care facilities are also going to be included in this first round of vaccinations. As this is being rolled out over the next several months, what should people know about their behavior? Once you’re vaccinated, do you still have to wear masks and socially distance? And if so, for how long?

It’s going to take months to vaccinate enough people in the community to achieve what we call herd immunity where we can finally take off our masks and hug one another again. We’re talking about 70-to-80 percent of the population before we can breathe a sigh of relief.

Also, we know the vaccine prevents COVID-19 disease, but we don’t know if it prevents you from getting infected and transmitting the virus to others. So even when you get vaccinated, you still need to mask and maintain social distancing until the vast majority of the community has been vaccinated. Hopefully, we’ll get that done by next summer.

What would you say to people who are on the fence about whether to get the vaccine or have already decided that under no circumstances will they get vaccinated?

I certainly understand that people have lingering questions. They may be worried that the process was rushed. They may be skeptical of the new technology involved with the Pfizer and Moderna vaccines, in particular.

But I can assure you, after having watched all nine hours of the expert panel discussion on the Pfizer vaccine last week, that brilliant minds considered all of the evidence to date and overwhelmingly agreed that the Pfizer vaccine is safe and effective. They are expected to do the same later this week with the Moderna vaccine.

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And not only will I happily raise my sleeve when it’s my turn to get the vaccine, I’m hoping that everyone will the do same so we can wake up from this nightmare.

A viewer writes, “Would your doctor contact you directly to schedule an appointment to get the vaccine?”

That’s a good question. Right now, hospitals are vaccinating their staff with direct contact with COVID-19 patients.

When it’s your turn to get vaccinated, I would imagine you would contact your primary care physician, a local pharmacy, or your local health department. There is also a website through the CDC called which will provide more information on where you can get vaccinated.

Both Frank and Paula want to know whether having allergies precludes them from getting the Pfizer vaccine.

Two people in the U.K. had significant allergic reactions to the Pfizer vaccine, prompting U.K. regulators to say that people with pre-existing severe allergic reactions should not get the vaccine at this time. However, the CDC recently said that people with a history of anaphylaxis to other vaccines or injections can still get the vaccine but should discuss the risks with their doctors and be monitored for 30 minutes after getting the shots. And people with allergies to food, latex, pollen, or other substances do not need to take special precautions and can get vaccinated.

Denise in Saugus writes, “The 2nd group to receive the vaccine lists the elderly. Would it be those over 70 or those over 60?”

According to the Massachusetts Department of Health, people 65 and older are included in Phase 2 of the vaccine rollout.

Laura asks, “I am 65 years and due to begin taking Prolia for my osteoporosis soon. Should I delay this 1st injection until after I receive a vaccine for Covid 19?”

Prolia is a medication used to treat osteoporosis and as far as I know, there is no reason why you can’t get your Prolia injection and still get the vaccine. But call your doctor to make sure.

Alese writes, “After I get the first shot, what if I can’t get the second in the 21-day period? Will I have to start over with shots?”

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The Pfizer vaccine is given 21 days apart. The Moderna vaccine, which is likely to become available in the coming weeks, is given 28 days apart. That’s the timing that was studied in the clinical trials, so we don’t know what happens if the second shot is delayed. I can’t imagine delaying the second shot by a couple of days will matter but try to schedule your vaccine when you can get your second injection on time.

Dr. Mallika Marshall