Today, children in the United States routinely get vaccines that protect them from more than a dozen diseases such as measles, polio, tetanus, diphtheria, and pertussis (whooping cough). Most of these diseases are now at their lowest levels in history, thanks to years of immunization. Children must get at least some vaccines before they may attend school.
Vaccines help make you immune to serious diseases without getting sick first. Without a vaccine, you must actually get a disease in order to become immune to the germ that causes it. Vaccines work best when they are given at certain ages. For example, children don't receive measles vaccine until they are at least one year old. If it is given earlier it might not work as well. The Centers for Disease Control and Prevention publishes a schedule for childhood vaccines.
Although some of the vaccines you receive as a child provide protection for many years, adults need immunizations too. (Source:Center for Disease Control and Prevention)
How Vaccines Work
Vaccines "teach" your body how to defend itself when germs, such as viruses or bacteria, invade it:
- They expose you to a very small, very safe amount of viruses or bacteria that have been weakened or killed.
- Your immune system then learns to recognize and attack the infection if you are exposed to it later in life.
- As a result, you will not become ill, or you may have a milder infection. This is a natural way to deal with infectious diseases.
- English: Frequently Asked Questions About Vaccines
- Español: Preguntas frequentes sobre inmunizaciones
Why We Need Vaccines
For a few weeks after birth, babies have some protection from germs that cause diseases. This protection is passed from their mother through the placenta before birth. After a short period, this natural protection goes away.
Vaccines help protect against many diseases that used to be much more common. Examples include tetanus, diphtheria, mumps, measles, pertussis (whooping cough), meningitis, and polio. Many of these infections can cause serious or life-threatening illnesses and may lead to lifelong health problems. Because of vaccines, many of these illnesses are now rare.
- English: Childhood Vaccines: What They Are and Why Your Child Needs Them
- Español: Vacunas en la niñez: lo que son y porqué su niño las necesita
- English: Vaccine-Preventable Childhood Diseases
- Español: Enfermedades y las vacunas que las previenen
Safety of Vaccines
Some people worry that vaccines are not safe and may be harmful, especially for children. They may ask their health care provider to wait or even choose not to have the vaccine. But the benefits of vaccines far outweigh their risks.
The American Academy of Pediatrics, the Centers for Disease Control and Prevention, and the Institute of Medicine all conclude that the benefits of vaccines outweigh their risks. (Source: U.S. National Library of Medicine)
2016 Recommended Immunization Schedules (Vacunas recomendadas para niños)
Click here to view the CDC's detailed information about immunizations and other precautions for travelers to other countries. Many immunizations should be received at least 1 month before travel.
Bring your immunization record with you when you travel to other countries. Some countries require this record.