Immunization facts for kids

A child being immunized against polio.

Immunization is a special way to protect your body from getting sick with certain diseases. It works by teaching your body's natural defense system, called the immune system, how to fight off germs before you even get sick.

Think of it like a training exercise for your immune system. When you get immunized, you receive a tiny, safe part of a germ, or a weakened version of it. This material is called an immunogen. It's not enough to make you truly sick, but it's enough for your immune system to recognize it.

Your immune system then learns how to create special "soldiers" (called antibodies) that can quickly attack and destroy that specific germ if you ever encounter it for real. This means if the actual germ tries to invade your body later, your immune system is ready and can fight it off quickly, often preventing you from getting sick at all. This process is also known as vaccination.

How Immunization Works

When your immune system meets a germ for the first time, it takes a while to figure out how to fight it. But once it learns, it remembers! Immunization gives your body a safe "first meeting" with a germ. This way, your body builds up its defenses without you having to suffer from the actual illness.

Why Immunization is Important

Immunization protects you from many serious diseases that can cause a lot of harm, like measles, mumps, rubella, polio, and tetanus. It also helps protect your community. When many people are immunized, it's harder for diseases to spread from person to person. This is called "herd immunity," and it helps protect those who cannot be immunized, like very young babies or people with certain health conditions.

Types of Immunization

There are different ways to get immunized:

• Vaccines: These are the most common type. They are usually given as a shot, but some can be given by mouth or as a nasal spray. Vaccines contain weakened or inactive parts of germs, or even just pieces of their genetic material.
• Antibodies: Sometimes, if someone is already exposed to a serious disease or has a weak immune system, they might be given antibodies directly. This provides immediate, but temporary, protection.

History of Immunization

People have tried to prevent diseases for hundreds of years. One of the earliest forms of immunization was called variolation, used against smallpox. People would deliberately expose themselves to a mild form of the disease to gain protection.

The first true vaccine was developed by Edward Jenner in 1796. He noticed that milkmaids who got cowpox (a mild disease) didn't get smallpox (a deadly disease). He used material from cowpox sores to protect people from smallpox, leading to the word "vaccine" (from "vacca," Latin for cow). Thanks to vaccines, smallpox was completely wiped out worldwide in 1980!

Common Immunizations for Kids

In many countries, children receive a schedule of immunizations from birth through their teenage years. These protect against a range of diseases, including:

• Measles, Mumps, and Rubella (MMR)
• Polio
• Diphtheria, Tetanus, and Pertussis (DTaP)
• Chickenpox (Varicella)
• Hepatitis B
• Human Papillomavirus (HPV)

These immunizations are very safe and effective. They are one of the best ways to keep you and your friends healthy and strong!

Images for kids

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  Medical student participating in a polio vaccine campaign in Mexico

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  This graph shows how immunization benefits not just the person getting the shot, but also the whole community by stopping diseases from spreading.

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  This graph illustrates how some immunization efforts can reduce a disease, but not completely get rid of it.

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  This graph shows how strong immunization campaigns can lead to a disease being completely wiped out, like smallpox.

See also

In Spanish: Inmunización para niños