BOSTON (CBS) — Dr. Mallika Marshall is answering your coronavirus vaccine-related medical questions. If you have a question, 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.

Tracy writes, “How bad are the side effects if you have COPD or have had a double bypass? I’m 53 with COPD and my mom is 70 with a double bypass.”

Having underlying lung or heart disease does not mean you’re going to have more or fewer side effects from the COVID-19 vaccines. Some people have no side effects at all. Younger people tend to have more side effects than older people. But it’s hard to predict who will have side effects or which side effects you’ll develop but usually, they are mild to moderate and last no more than 24-36 hours. Please get your vaccines.

George asks, “Am I correct in assuming that the air dryers in many (if not most) of public restrooms potentially do more harm than good, actually blowing the virus onto your hands?”

Hand dryers in public restrooms are unlikely to spread the virus to others. After thoroughly washing your hands, you can either use paper towels or electric hand dryers to safely dry your hands.

Deborah writes, “I received my second Covid vaccine on March 29th then found out a few days later that I had shingles. Will having Shingles have any negative effect on my vaccine. Will I have to get another one?”

Having shingles should not affect the effectiveness of the vaccine. You do not need to get another vaccine for that reason.

Kate in Natick asks, “I received my second dose of the Pfizer vaccine on Friday. On Monday I was at my orthopedics office and received a cortisone shot for bursitis in my hip. Will the steroid shot reduce the efficacy of my vaccine? I am worried.”

While some experts recommend postponing a cortisone injection after getting a COVID vaccine due to a theoretical possibility that it could blunt the immune response, it’s unlikely to have a large effect. Please don’t worry and enjoy the fact that soon you’ll be fully vaccinated!

Dr. Mallika Marshall