What Are Vaccinations?

Since Edward Jenner created the world’s first vaccine (for smallpox) in the 1790s, vaccinations have been used to help prevent the spread of many contagious and potentially fatal diseases. Vaccines are biological formulations, often made with a weakened or killed disease-causing organism, that produce immunity against certain diseases when administered by injection, aerosol, or oral drugs.

Vaccines undergo stringent review involving clinical and lab data to ensure their safety, efficacy, potency, and purity before they are approved. Despite this, there is a growing anti-vaccination movement that contributed to one in 10 infants worldwide receiving zero vaccinations in 2016. While there are some risks associated with all medical products, including vaccines, the U.S. Food and Drug Association (FDA) considers approved vaccines to be both safe and important for stopping the spread of disease.

Vaccinations by Age

Getting a vaccination means preventing disease and illness before you’re exposed. That’s why it’s important to know which vaccines you and your family need and when you need them. By following a vaccination schedule recommended by the Centers for Disease Control and Prevention (CDC), World Health Organization (WHO), or your doctor, you can help protect your health and the health of others.

Vaccines for Infants and Children (Birth to Age 12)

The vaccination schedule from birth through childhood is designed with safety and convenience in mind, since this age range is most at risk of complications from a wide variety of diseases.

Vaccination Schedule for Children

Diphtheria, tetanus, and acellular pertussis (DTaP)
The bacterial diseases diphtheria (infection of the throat) and pertussis (whooping cough) are spread through close contact with an infected person, while tetanus (lockjaw) enters the body through a cut or a wound. Children should get five doses of the DTaP vaccine, with one dose administered at each of these ages: two months, four months, six months, 15-18 months, and four to six years.
Haemophilus influenzae type b (Hib)
The bacteria haemophilus influenzae (H.influenzae) can cause ear infections and severe bloodstream infections. The Hib vaccine is recommended for all children younger than five years, though it’s typically administered as early as two months.
Hepatitis A (HepA)
Hepatitis A is a viral liver disease transmitted through direct contact with an infectious person, or by ingesting contaminated water and food. HepA vaccines should be given between 12-23 months.
Hepatitis B (HepB)
Hepatitis B is a viral infection that attacks the liver, and is transmitted through the body fluid or blood of an infected person. The first dose of this vaccine should be given at birth, followed by a second dose after one or two months.
Human papillomavirus (HPV)
There are more than 100 types of human papillomavirus (HPV), which can cause genital warts and, with at least 13 types, cervical cancer. All girls and boys aged 11 – 12 years should get the recommended HPV vaccination series, though it can be started at as young as nine years.
 Inactivated poliovirus (IPV / Polio)
Polio is an infectious disease caused by a virus in the throat and intestinal tract. It is spread via contact with the stool or oral/nasal secretions of an infected person. Children get four doses of the IPV vaccination at these intervals: two months, four months, between six and 18 months, and a booster at four to six years.
 Influenza (IIV)
 Caused by the influenza virus, the “flu” is one of the most common infectious diseases, spread mainly by coughing, sneezing, and close contact. Everyone should get a flu vaccination annually beginning at six months of age.
Measles, mumps, rubella (MMR)
Measles, mumps, and rubella are serious, highly contagious diseases spread through the air. Two doses of the MMR vaccine should be given, the first when a child is 12-15 months old, and the second at four to six years.
Meningococcal (Hib-MenCY; MenACWY-D; MenACWY-CRM)
To help prevent meningococcal disease, caused by Neisseria meningitidis bacteria, all children aged 11-12 should be vaccinated with a meningococcal conjugate vaccine, with a booster dose recommended at 16 years.
Pneumococcal conjugate (PCV13)
Spread through close contact with an infected person, pneumococcal disease causes ear infections, and can lead to more serious lung infections (pneumonia), blood infections (bacteremia), and brain/ spinal cord infections (meningitis). Five doses of PCV13 should be administered to children at two, four, six, and 12–15 months of age.
Pneumococcal polysaccharide (PPSV23)
Anyone aged two or older with certain long-term health problems or a weakened immune system should get the PPSV23 vaccine, which protects against 23 types of pneumococcal bacteria.
Rotavirus (RV)
Rotavirus is a severe infection that can cause abdominal pain, diarrhea, vomiting, and fever. At age one to two months, most babies should get either two or three doses of the RV vaccine depending on which brand of vaccine is used.
Tetanus, diphtheria, and acellular pertussis (Tdap)
This booster dose for tetanus, diphtheria, and pertussis is given at age 11 for continued protection.
Varicella (VAR)
Chickenpox is an extremely contagious disease caused by the varicella-zoster virus. Symptoms of this virus include blister-like rashes, itching, fatigue, and fever. Two doses of the VAR vaccine (the first at 12-15 months, and the second at four to six years) are effective at preventing the disease in 90% of cases.

Vaccines for Teenagers (age 13 to 18)

Teenagers who missed any of their childhood vaccinations or may be traveling outside of the U.S. should visit their doctor to discuss having them administered. Additionally, all teenagers should receive a flu vaccination every year.

Vaccines for Young Adults (age 19 to 24)

While most vaccinations are received early in childhood, college students, military recruits, and other young adults require them, too. Since your college or armed services branch may require specific vaccinations, it’s wise to contact them directly for more specific direction.

In general, young adults age 19-24 should be up to date on all previously mentioned vaccinations.

Vaccination Schedule for Young Adults

State requirements vary when it comes to this protection against bacterial meningitis, but it’s generally recommended for all first-year college students living in residence halls. Those who received the meningococcal conjugate before their 16th birthday should get a booster dose before going to school.
Young adults who didn’t receive Tdap as a preteen or teen should receive a single dose of this vaccine to protect against tetanus, diphtheria, and pertussis.
Young adults who didn’t start or finish the HPV vaccine series at age 11 or 12 are urged to do so.
Seasonal Flu Vaccination
All young adults should protect themselves against the flu by getting vaccinated yearly.

Adults (age 19 and older)

All adults should have had the aforementioned vaccinations. If you missed any, talk to your doctor about your options. In addition, seasonal and periodic vaccinations also recommended for adults include:

  • Flu vaccine: All adults should receive a yearly flu vaccination, especially pregnant women, older adults, and those with chronic health conditions.
  • Tdap: Adults should get one dose of the tetanus and diphtheria (Td) vaccine every 10 years. If you didn’t get the Tdap vaccination during adolescence, you should get one dose in place of the Td vaccine to protect against whooping cough. You can get the Tdap vaccination at any time, regardless of when you last had Td.
  • HPV: All women under the age of 27 and all men under the age of 22 should be vaccinated for the human papillomavirus. Men aged 22-27 who have compromised immune systems or have had sexual intercourse with other men should also be vaccinated.

In addition, some vaccinations are recommended for adults due to particular job or school-related requirements, health conditions, or other factors. These include MMR, VAR, Herpes Zoster Vaccine (HZV), HPV, PCV13, PPSV23, HepA, HepB, MenACWY/MPSV4, MenB, and Hib.

Vaccines for Seniors (age 60 and older)

Seasonal flu vaccinations are especially important for older adults, who often have a higher risk of complications from the disease. In addition to this, all seniors should have:

  • A Td or Tdap vaccination to protect against tetanus, diphtheria, and pertussis
  • The pneumococcal vaccinations
  • A dose of the Zoster vaccine, which protects against shingles

Special Considerations for Vaccination

Depending on your circumstances, you doctor may recommend you receive additional vaccinations throughout your life, or that you don’t receive certain vaccines.

Pregnant women

The CDC recommends administering the flu vaccine (during any trimester) and Tdap (early in third trimester) during each pregnancy.

Compromised Immune Systems

Adults with immunocompromising health conditions should generally avoid live vaccines, such as the MMR vaccine. Close contact with people who have received a live vaccine in the past two to three weeks should also be avoided.

Traveling to Foreign Countries

Four to six months before you travel outside the U.S, be sure to check that you’re up-to-date on all routine vaccinations. Schedule an appointment with your healthcare provider to discuss the recommended vaccines for the countries you plan to visit.

It’s widely believed that vaccines represent the single greatest prevention against the spread of disease. If you have any questions or uncertainties about vaccines, or for more information about the vaccination schedule, contact your doctor or healthcare professional.