Image for kids and exercise article A vaccine, or immunization, is a medication given to a person so that the person produces antibodies against a certain infection. These antibodies then serve to help prevent the infection.

In the US, vaccines have resulted in record-low levels of certain childhood diseases. Vaccines do not only protect the person they are given to, but also the population at large, since they work to reduce the general prevalence of once-common infections.

Vaccine-Preventable Infections

The following infections can be prevented by vaccination:

  • Diphtheria—a throat infection caused by bacteria that may result in breathing problems, coma, and death if not treated
  • Haemophilus influenzae type B—a bacterial infection occurring primarily in children; if severe, can lead to meningitis, death, and permanent brain damage
  • Hepatitis A—an infection caused by the hepatitis A virus that affects the liver
  • Hepatitis B—an infection caused by the hepatitis B virus that can lead to scarring of the liver and liver cancer
  • Human papillomavirus (HPV)—the virus that causes some warts and is associated with cervical cancer
  • Influenza—a common viral infection that most commonly occurs during the winter months
  • Measles—a viral respiratory infection with a specific rash that may lead to diarrhea, ear infections, pneumonia , swelling of the brain, seizures, and death
  • Meningococcus—a cause of bacterial meningitis, a serious, often fatal, disease
  • Mumps—a viral infection of the lymph nodes that may lead to meningitis, inflammation of the testicles, ovaries, or pancreas, and permanent deafness
  • Pertussis (whooping cough)—a bacterial respiratory infection that may lead to pneumonia, swelling of the brain, and death, especially in infants
  • Pneumococcal disease—a bacterial infection that is a common cause of pneumonia in adults but may lead to ear infections and meningitis in children
  • Polio—a viral infection of the nervous system that can lead to disability and death
  • Rotavirus—major cause of potentially life-threatening gastroenteritis (vomiting, diarrhea)
  • Rubella (German measles)—a viral respiratory infection that, when contracted by a pregnant woman, can cause birth defects, including deafness, cataracts, heart abnormalities, intellectual disability, and liver and spleen damage
  • Tetanus (lockjaw)—a bacterial infection of the nervous system that can result in death
  • Varicella (chickenpox)—a herpes virus that may lead to pneumonia and encephalitis (swelling of the brain)

Childhood Vaccines

The following vaccines are recommended in children who are at average risk for these infections:

  • DTaP—3 vaccines in one shot given in a series of 5 doses; protects against diphtheria, tetanus, and pertussis; Tdap is a vaccine recommended as a booster dose in early adolescence
  • HepA—given in a series of 2 doses to protect against hepatitis A
  • Hep B—given as a series of 3 shots to help prevent hepatitis B
  • Hib—given as a series of 3 or 4 shots to help prevent Haemophilus influenza type B
  • HPV—given as a series of 3 shots to help prevent HPV, which can cause genital warts and cervical cancer
  • Influenza—given annually to help prevent the flu (Some children aged 6 months to 8 years old may need a series of 2 shots.)
  • MCV4—one shot and a booster dose given to protect against bacterial meningitis from Meningococcus
  • MMR—given as 2 shots to protect against measles, mumps, and rubella
  • PCV—given in a series of 4 doses to protect against the pneumococcal bacteria
  • Polio vaccine—given in a series of 4 doses to prevent polio
  • Rotavirus vaccine—given in a series of 2 or 3 doses to protect against rotavirus
  • Varicella—given as 2 shots to help prevent chickenpox

Childhood Immunization Schedule

The table below summarizes when children of average risk should receive certain vaccinations. You may print the table and use the “Date received” column to track when your child receives each vaccine.

Age Recommended vaccines Date received
  • HepB (first dose)
1-2 months
  • HepB (second dose)
2 months
  • DTaP (first dose)
  • Hib (first dose)
  • PCV (first dose)
  • Polio vaccine (first dose)
  • Rotavirus vaccine (first dose)
4 months
  • DTaP (second dose)
  • Hib (second dose)
  • PCV (second dose)
  • Polio vaccine (second dose)
  • Rotavirus vaccine (second dose)
6 months
  • DTaP (third dose)
  • Hib (third dose)
  • PCV (third dose)
  • Rotavirus vaccine (third dose)
Yearly after 6 months
  • Influenza (Some children aged 6 months to 8 years old may need second dose 4 weeks after the first dose.)
6-18 months
  • HepB (third dose)
  • Polio vaccine (third dose)
12-15 months
  • Hib (fourth dose)
  • MMR (first dose)
  • PCV (fourth dose)
  • Varicella (first dose)
12-23 months
  • HepA (second dose given 6-18 months after first dose)
15-18 months
  • DTaP (fourth dose)
4-6 years
  • DTaP (fifth dose)
  • Polio vaccine (fourth dose)
  • MMR (second dose)
  • Varicella (second dose)
11-12 years
  • Tdap (booster shot to protect against tetanus, diphtheria, and pertussis)
  • HPV (three doses)
  • MCV4
16-18 years
  • MCV4 booster

Certain “high-risk” children may need to receive additional vaccinations and/or doses, or certain vaccinations at an earlier. Also, if your child missed one or more vaccines, the Centers for Disease Control and Prevention (CDC) has recommended times for “catch-up” immunizations. Talk to the doctor to find out if this applies to your child.

Some Children Should Not Be Vaccinated

Childhood vaccines are generally very safe. Some children may experience mild adverse events at the time of the vaccine, including fever, soreness at the vaccine site, or a lump under the skin where the shot was given. Some reactions (MMR) do not appear until weeks after the vaccine is given.

The small risk of serious adverse events is far outweighed by the disease-preventing benefits of vaccines in most cases. However, there are some situations in which children should not receive certain vaccines. Examples of these situations include children who:

  • Had a life-threatening allergic reaction to a component in the vaccine
  • Are severely ill (wait until the child has recovered)
  • Are taking medications to suppress the immune system
  • Have certain types of cancer or other diseases

Talk with the doctor to find out if it is safe to have your child vaccinated.