Vaccine basics

Vaccines are some of the safest medicines that exist. Every vaccine undergoes a lot of testing before it becomes available. Vaccine safety continues to be monitored the whole time that a vaccine is in use.

Most side effects from vaccines are very minor, such as a sore arm or fever, and they usually don’t last very long. There is a small risk that serious problems could occur after getting a vaccine, but the potential risks from a vaccine-preventable disease are much more serious.

Flu vaccine (flu shot)

There’s a lot of information out there on the flu vaccine (flu shot). We are here to help clear up some of the common myths about flu shots so that you can make the choice that’s right for you.

Can the flu shot give you the flu?

No. The flu shot doesn’t contain a live virus, so it will not make you sick. You might feel mild, short-term side effects, like a sore arm or redness where you got the shot, but that is all.

If I’m healthy should I still get the flu shot?

Yes. Anyone can get the flu, and it can be serious even for healthy people. Getting the flu shot helps protect you and others around you – especially children and older people who might be more vulnerable.

If I got the flu shot last year, do I need to get it again this year?

Yes. The flu virus changes every year, and the flu shot is updated every year to match the current flu strain. The best way to avoid getting the flu is by getting your annual flu shot.

Some other ways to help lower your risk of getting the flu include:

  • Frequently washing your hands with soap and water for 20 seconds
  • Using alcohol-based hand sanitizer when you aren’t near a sink
  • Avoid touching your eyes, nose, and mouth in public
  • Covering your coughs and sneezes using a tissue or the crook of your elbow
  • Staying home when you feel sick
  • Getting plenty of rest

COVID-19 vaccine

Everyone over the age of 6 months is encouraged to get the COVID-19 vaccine. Getting the vaccine is the best way to prevent getting sick with COVID-19.

Click here for more information from the New York State Department of Health on COVID-19 vaccination for children and adults, including pregnant people.

Vaccine information for you and your family

Unvaccinated and under-vaccinated children can spread diseases to other children, including those who may have been vaccinated. Vaccines have lowered the number or even stopped outbreaks of certain diseases like measles, polio, and smallpox. Vaccines protect children who have been vaccinated and help start "community immunity" - when most of a population has been vaccinated against a disease so everyone is more protected.

Prenatal vaccines

Getting vaccinated is one of the most important things that you can do to protect your health  while you are pregnant. Vaccines have been safely given to millions of pregnant people.

After you get a vaccine during pregnancy and your body creates antibodies, some of those antibodies pass to the fetus. This means the baby will have antibodies to protect against disease after birth. Antibodies are a safe, normal reaction to a vaccine. They protect your baby during the first few months of life until your baby can be vaccinated.

Content from the American College of Obstetricians & Gynecologists, available here.

More information about vaccines for adults, children and expecting moms is available here.

Every vaccine ingredient serves a purpose

To provide immunity.

We become immune to (or protected from) a disease when our bodies create specific antibodies to fight that disease. Vaccines contain ingredients that help your body build this immunity.

To keep the vaccine safe and long-lasting.

Vaccines need to be safe and effective. Certain ingredients help keep vaccines safe from contamination and toxins. Others, like stabilizers, help vaccines stay effective for a long time.

To make the vaccine more effective.

All vaccine ingredients help to make a vaccine as effective as possible, while being safe. Ingredients like aluminum salt help boost the body's response to the vaccine.

Ingredients found in some vaccines

Stabilizers

  • Purpose: To keep the vaccine effective after manufacturing
  • Most commonly found in: Jell-O®, naturally in the body
  • Examples: Sugars, gelatin

Adjuvants

  • Purpose: To help boost the body's response to the vaccine
  • Most commonly found in: Drinking water, infant formula, and some health products such as antacids, buffered aspirin, and antiperspirants
  • Examples: Aluminum salts

Residual inactivating ingredients

  • Purpose: To kill viruses or inactivate toxins during the manufacturing process
  • Most commonly found in: Naturally in the human body, fruit, household furnishings (carpets, upholstering)
  • Example: Formaldehyde

Residual cell culture materials

  • Purpose: To grow enough of the virus or bacteria to make the vaccine
  • Most commonly found in: Eggs, and foods that contain eggs
  • Examples: Egg protein

Residual antibiotics

  • Purpose: To prevent contamination by bacteria during the vaccine manufacturing process
  • Most commonly found in: Common antibiotics. Antibiotics that people are most likely to be allergic to, like penicillin, aren't used in vaccines.
  • Examples: Neomycin, Kanamycin, Streptomycin

Preservatives

  • Purpose: To prevent contamination
  • Most commonly found in: Some kinds of fish
  • Example: Thimerosal (only in multi-dose vials of flu vaccine)

Most vaccines don't contain any mercury

Most vaccines do not have any mercury in them. However, multi-dose flu vaccines and one type of tetanus-diphtheria (Td) vaccine contain a small amount of thimerosal. Thimerosal contains a form of mercury (ethylmercury) that does not cause mercury poisoning and is safe for use in vaccines. Flu and Td vaccines are also available in thimerosal-free versions.

Different types of vaccines work in different ways

Vaccines can help protect against certain diseases by imitating an infection. This helps teach the immune system how to build immunity to fight off a future infection. Different vaccines provide immunity in different ways.