What should you know about different mRNA vaccines?

The mRNA is a short-lived message that helps some cells make a harmless piece or feature associated with a germ. Your immune system studies that feature and makes a response, including immune memory. The message is then broken down; it does not become part of your DNA. Vaccines differ in the germ or strain they target, the formulation used to protect the message, and the schedule recommended for the person receiving it.

Protection is directed at the infection named for that vaccine. A vaccine for one illness should not be assumed to protect against unrelated infections. Guidance may also vary with age, pregnancy, previous doses, immune conditions, and local recommendations.

Bring your vaccination record and mention previous reactions, allergies, pregnancy, immune-suppressing treatment, or a current illness. Ask which product is offered, whether it is suitable after earlier doses, and when any further dose is due. A sore arm, tiredness, headache, chills, or a mild fever can occur as the immune system responds. Rest, fluids, and the advice given by your clinician may help.

Seek urgent help for trouble breathing, swelling of the face or throat, widespread hives, fainting, or severe weakness after vaccination. Contact a clinician promptly for symptoms that are worsening, unusual for you, or not settling, especially if you have a condition or treatment that affects immunity.

Which mRNA vaccine is recommended for me, and what infection does it cover? Does my medical history change the schedule? How should I respond if I develop a fever or feel unwell afterward?