The U.S. Centers for Disease Control and Prevention (CDC) has set up recommended schedules for immunizations in childhood, adolescence, and adulthood. Most people born in the United States are vaccinated against many diseases in the weeks and months after their birth. Even if you got these vaccinations, most of them do not last forever and you need to get vaccinated again to maintain your immunity. See the end of this article for links to the recommended immunization schedules for each age group.

The CDC recommends the following vaccinations for people after the age of 18:

• Diphtheria, pertussis, tetanus (DPT) vaccine once every 10 years or after possible tetanus exposure.
• Human papillomavirus (HPV) vaccine for young women, given in three doses over six months.
• Measles, mumps, rubella (MMR) vaccine once or twice during adulthood
• Influenza once each year.
• Pneumococcal vaccine once after age 65.
• Zoster vaccine (protects against shingles) once after age 60.
• For people with certain risk factors, hepatitis A, hepatitis B, and meningococal vaccines are also recommended.

Before you travel to another country, especially one in the developing world, check with your doctor or contact the local public heath department for information about which vaccinations may be recommended or required for travel in that region.