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.

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Joseph says, “I had Guillain Barre Syndrome back in 2017 and was advised to never get the flu shot. My concern is will the COVID-19 shot will bring on GBS.”

The only coronavirus vaccine available in the U.S. which has been associated with a very small number of cases of Guillain-Barre is the J&J vaccine. Neither of the mRNA vaccines (Pfizer or Moderna) has been associated with the syndrome. I would discuss your concerns with your personal physician, but according to the CDC, you are probably fine getting an mRNA vaccine.

Marti in Scituate writes, “I received the vaccine and was given a CDC card. My husband’s vaccine was registered on his medical record, but he was not given the CDC card. Could this present problems for future travel if proof of vaccination is required?”

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I would take a photo of your vaccination card and keep it on your smartphone. That’s what I’ve done for me and my family. For your husband, print out a copy of your husband’s vaccines from his electronic medical record and scan that or take a screenshot of it on a smartphone. I wish there was a more centralized process both here in Massachusetts and nationwide.

Carole writes, “I was wondering why the Covid-19 vaccine uses such a long needle? I have not been vaccinated and probably won’t due to my intense fear of needles.”

The needles used for the COVID-19 vaccines are typically 1” to 1 ½“ long depending on the size of the patient. This is the same length used for other vaccines like the flu vaccine. But needle phobias are real, so please talk to your doctor about how to overcome your fears so you can get vaccinated against this potentially deadly infection.

Isabel has a concern about the Delta variant. She writes, “There are neighbors in Boston and coastal towns that receive substantial numbers of out-of-state tourists whose vaccination status is unknown. What would you recommend vaccinated residents do in these areas?”

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If you’re fully vaccinated and not immunocompromised, you should be well protected from getting seriously ill from COVID-19, even from the Delta variant. However, if you’re at high risk of COVID-19 complications, I would remain vigilant which means wearing your mask when in large crowds or when in the presence of large numbers of potentially unvaccinated people.

Dr. Mallika Marshall