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Vaccines are a breakthrough of modern medicine. They helped get rid of smallpox in the U.S. and have all but eliminated other serious diseases like polio. But decades later, some people are opting out of vaccinations. And serious cases of measles, whooping cough, and other dangerous diseases are increasing.
Unfortunately, there are many myths about vaccines. One is that they cause autism, disabilities, and other medical issues. But there’s no scientific evidence that supports these claims, and much of the information that’s shared online is inaccurate.1,2
To help keep yourself and your loved ones safe, it’s important to understand:
- How vaccines work
- Why vaccines are important
- The difference between vaccines, shots, and immunizations
What are vaccines, and why are they important?
Vaccines are one of the best ways to protect yourself and your loved ones from serious illness. When you get a vaccine, your immune system produces antibodies to help your body recognize and fight a disease if you’re ever exposed. This significantly lowers your chances of getting sick and spreading the disease to others.
The Centers for Disease Control and Prevention estimates that vaccinations will prevent nearly 30 million hospitalizations and more than 1 million deaths among children born between 1994 and 2021.3 And vaccines have prevented countless cases of dangerous and deadly diseases around the world.
What’s the difference between vaccines, shots, and immunizations?
People often refer to vaccines, shots, and immunizations as if they’re all the same. But each term is one part of a process that builds your body’s defenses against a specific disease or illness.
- Vaccines are the treatment you receive to build immunity. Some vaccines are given as a mist you can inhale or a medicine you can drink. But the most common way to get a vaccine is with a shot, also called an injection.
- A shot is when a needle and syringe inject a liquid substance into your body. Sometimes it’s a vaccine, like the flu shot or tetanus shot. It’s also common for medicines like insulin or antibiotics.
- Immunization is the process of becoming protected from — or immune to — a disease or illness. Getting vaccinated is the best way to build immunity against some serious diseases.
It can also prevent the spread of deadly diseases to other people. This helps build herd immunity — when a community of people is protected from a contagious disease. Herd immunity is how vaccines got rid of smallpox.
How is a vaccine different from a medicine?
Vaccines are a type of medicine. They’re tested and approved like any drug with the Food and Drug Administration. But a few things make vaccines different from many other medicines.
- Ingredients — Vaccines are almost always built from biological ingredients. So, like milk or eggs, they can expire. Other drugs are often built from chemicals that make them easier to store and duplicate.
- Dosage — Vaccines are “scheduled,” with a set dosage for everyone. Other medicines are more individualized — how much you take can vary from person to person.
- Timing — Vaccines help protect communities from contagious disease and build herd immunity. So, you take them before you get sick. Other kinds of medicine can be used to diagnose, cure, and treat conditions you already have.
Common types of vaccines
Many of the vaccines you get as a child protect you from specific illnesses your whole life. But you may need to repeat other types of vaccines — like the ones for the flu and tetanus. Some of the most common vaccines include:
- Chickenpox (varicella)
- COVID-19 (coronavirus disease)
- Flu (influenza)
- Hepatitis A
- Hepatitis B
- Hib (haemophilus influenzae type b) disease
- HPV (human papillomavirus)
- Measles, mumps, and rubella (MMR)
- Meningococcal disease
- Pneumococcal disease
- Polio
- Rotavirus
- RSV (respiratory syncytial virus)
- Tetanus, diphtheria, and pertussis (including whooping cough)
- Zoster (shingles)
Not sure which vaccine you need?
Talk to your doctor if you have any questions about vaccinations. Based on your health history, they can make suggestions and address your concerns. You should also let them know if you’re planning to travel outside the U.S. They may recommend certain vaccines for your destination and can give you more tips for preparing for a healthy trip.
For general guidance, review the CDC’s latest immunization schedules for adults and children.