Vaccines are a tool we use to protect people from diseases that can spread easily and make many people sick. Some of these diseases can even be deadly.
Vaccines are usually given as a shot, but some can be taken by mouth.
How do vaccines work?
Vaccines train your immune system to fight off certain viruses or bacteria—kind of like a practice run before the real thing. The ingredients in vaccines provide immunity, keep the vaccine safe and long-lasting, and make them more effective. Vaccines contain only killed or weakened forms of germs like viruses or bacteria, so they do not cause the disease. When administered, vaccines stimulate the body’s immune system to recognize and fight these germs, creating antibodies that provide protection against future infections. This process helps prevent widespread outbreaks of serious illnesses and contributes to overall public health.
Some diseases are more common in certain parts of the world. How many people in a community are vaccinated also affects how fast a disease can spread.
When more people get vaccinated, it helps protect everyone. This is called herd immunity.
What is herd immunity?
Herd immunity happens when enough people in a community are vaccinated so that a disease can’t spread easily. For example, to stop measles from spreading, about 95% of people in a community need to be vaccinated.
How do I know a vaccine is safe?
Vaccines go through many tests before they are approved for use. These tests make sure they are safe and work well.
After approval, the CDC keeps track of vaccine safety through a system called VAERS. Anyone can report a side effect there.
Serious side effects are very rare. For most people, the benefits of getting vaccinated are much greater than the risks of getting the disease.
Talk to your Care Team about which vaccines are right for you. Let them know if you have any health conditions, especially if you are pregnant or have a weakened immune system.
You can also read more from trusted sources like the CDC’s Vaccine Information Sheets, which we have at our health center and online.
What side effects can I expect?
Most people have mild side effects like:
- A sore arm
- A low fever
- Body aches
These are normal and show that your body is learning how to fight the disease. Side effects usually go away within 24 hours. If needed, you can take Tylenol to feel better.
Why should I get vaccinated?
Vaccines save lives. The World Health Organization says childhood vaccines save over 4 million lives every year.
Pneumococcal vaccines have saved over 1.6 million lives since 2000.
Hepatitis B vaccines help prevent liver cancer by stopping long-term infections.
Getting vaccinated protects you and also helps protect people who are more at risk—like babies, older adults, pregnant people, and those with weak immune systems. By becoming immunized, you can protect yourself and those around you as not everyone is vaccinated such as young babies.
Why do some vaccines need more than one dose?
Some vaccines need more than one dose to build strong, long-lasting protection. These are called vaccine series.
Vaccines like MMR, HPV, Hep A, Hep B, DTaP, and IPV often need multiple doses.
Other vaccines, like the flu or COVID vaccines, may change over time. That’s why you might need a new dose each year to stay protected.
