Vaccines protect children from devastating or fatal diseases

Get the facts and download current immunization schedules.


Vaccines protect children from getting sick from many crippling or deadly illnesses. Thanks to decades of immunization, diseases like measles and polio are mostly a thing of the past in the U.S.

“Despite what you may have heard, vaccines are quite safe for children,” says Jeffrey Kahn, M.D., Director of Infectious Disease at Children's Health. “In fact, the risks to your child from catching the diseases vaccines prevent far outweigh any threat posed by the vaccines themselves.”

Why children need vaccines

During their first few weeks of life, babies have some protection against germs that cause disease. The mother passes this natural immunity to her child through the placenta just before birth. Unfortunately, this protection quickly goes away and puts the infant at risk for dozens of potentially dangerous diseases. That's where vaccines come in. Vaccines "train" your child's own immune system to fight off invading viruses and bacteria.

How vaccines work

Vaccines work by exposing your child to a small, safe amount of a weakened or dead virus or bacteria. If your child comes in contact with that particular germ in the future, their immune system will recognize it and rally to fight it off. Kids who have received immunizations will either not become sick at all or get a milder form of the illness. Vaccines are a natural way to protect children from infectious diseases.

When should children get their vaccines?

New vaccines are developed and introduced every couple of years or so. See current vaccination schedules by age groups, as recommended by the Centers for Disease Control and Prevention (CDC).

Here are some of the common types of vaccines and the diseases they protect against:

  • The COVID‑19 vaccine is very effective at preventing severe illness from COVID‑19. The CDC recommends that everyone ages 6 months and older should get the COVID‑19 vaccine on a routine basis.
  • The DTaP vaccine protects against three separate illnesses: diphtheria, tetanus and pertussis. It's given in a series of five shots.
    • Diphtheria is bacterial infection that attacks the throat and heart. It can lead to heart failure and death.
    • Tetanus is a deadly disease of the central nervous system that causes severe muscle spasms. It is commonly called "lockjaw."
    • Pertussis, or whooping cough, causes severe coughing that makes it hard for your child to breathe, eat or drink. It can lead to pneumonia, convulsions, brain damage and even death.
  • The Hep B vaccine helps prevent hepatitis B virus (HBV). The vaccine is given in a series of either three or four shots.
    • Hepatitis B is a liver infection that can cause liver cancer.
  • The Hib vaccine helps prevent Haemophilus influenzae type b. The Hib vaccine is administered in a series of three or four shots.
    • Haemophilus influenzae type b is a common childhood disease that can lead to pneumonia, meningitis or severe throat infections.
  • The IPV (inactivated poliovirus) vaccine prevents polio. Your child will receive a series of four IPV shots.
    • Once common in children, polio has been nearly eradicated in the western world thanks to the vaccine. Polio can cause paralysis or even death. There is no cure.
  • The meningococcal conjugate vaccine (MCV4) protects against four different strains of bacterial meningitis. Children between 11 and 12 years old should get the MCV4 vaccine.
    • N. meningitidis is a type of bacteria that causes infections of the fluid surrounding the brain and spinal cord. Meningitis can cause blindness or brain damage.
  • The MMR vaccine is another 3-in-1 immunization that protects against the measles, mumps and rubella. It's given in two shots.
    • Measles causes cough, fever, rash and runny nose. Severe cases can lead to ear infections, pneumonia, brain swelling and death.
    • Mumps causes headache, fever and swelling of the saliva glands. Mumps can cause meningitis (an infection of the brain and spinal cord). It can lead to infertility in boys.
    • Rubella, or German measles, causes a rash, fever and swelling of glands in the neck.
  • The pneumococcal conjugate vaccine (PCV) protects against a bacteria that causes ear infections. Infants and toddlers receive four doses of the PCV vaccine.
    • The pneumococcal conjugate bacteria can cause serious illnesses including meningitis and infections of the bloodstream.
  • The rotavirus vaccine (RV) protects against two different types of rotavirus. Depending on your doctor's recommendation, your infant will receive either a two or three shot series.
    • Rotavirus causes diarrhea and vomiting in babies and young children. It may cause dehydration in severe cases as well.
  • The varicella vaccine prevents chickenpox. Children 12 months of age or older are given a single dose.
    • The varicella zoster virus (VZV) that causes chickenpox is highly contagious. It results in itchy blisters that can leave pockmarked scars. Rarely, it can lead to more severe illness or even death.
  • The HPV vaccine protects against the human papillomavirus (HPV). It’s given in a series of two shots at least six months apart. A three-shot series may be recommended for those with weakened immune systems or for those over 15 years old.
    • HPV is a common virus that can cause cervical cancer in women and genital warts in women and men.

What are the risks from vaccines?

Modern vaccines are safer than ever. But, as with any medication, vaccines do carry a small risk of harm, including severe allergic reactions.

Common reactions to vaccines may include soreness (at the injection site), fussiness or a decreased appetite. More serious reactions such as fatigue, fever and vomiting are rare. Severe reactions including high fever, seizures or allergic reactions are more rare still. Death from immunizations is extremely uncommon. Mild symptoms can be treated at home with an aspirin-free pain reliever. If your child experiences serious or severe reactions, contact your pediatrician.

What about the Autism debate?

Some parents don't let their child get the measles, mumps and rubella (MMR) vaccine because of autism concerns. But that choice can lead to much more than a bumpy, red rash. Encephalitis, an inflammation of the brain, can occur, according to Dr. Kahn. “There is no scientific or medical evidence that supports vaccines causing autism. At least 14 studies have definitely demonstrated no causal link.”

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