Immunity and vaccination are essential concepts that explain how our body protects itself from diseases. Every day, our body is exposed to harmful microorganisms such as bacteria, viruses, and fungi. The ability of the body to fight these disease-causing germs is called immunity.
Immunity is provided by the immune system, which is made up of special cells, tissues, and organs. One of the most important components of the immune system is the white blood cells (WBCs). These cells recognize harmful germs, destroy them, and protect the body from infections.
While some immunity is present naturally from birth, other types of immunity develop after exposure to diseases or through vaccination. Vaccination is a scientific method of helping the body develop immunity without causing the actual disease. Vaccines contain weakened or dead germs that stimulate the immune system to produce antibodies, which protect the body in the future.
Immunity and vaccination together play a crucial role in preventing serious and life-threatening diseases such as measles, polio, tetanus, and tuberculosis. They not only protect individuals but also help protect communities by reducing the spread of infections.
This article is a complete, student-friendly guide that explains:
- Meaning of immunity
- Role of white blood cells
- Types of immunity
- Vaccination and how it works
- Importance of vaccines
- Difference between natural and acquired immunity
What Is Immunity?
Immunity is the ability of the body to resist and fight infections caused by germs.
Functions of Immunity
- Protects the body from diseases
- Destroys harmful microorganisms
- Helps the body recover from illness
- Provides long-term protection
Immune System – The Body’s Defense System
The immune system is a network of:
- White blood cells
- Antibodies
- Lymph nodes
- Organs like spleen and bone marrow
Together, they defend the body against infections.
Role of White Blood Cells (WBCs)
White blood cells are the soldiers of the immune system.
Functions of WBCs
- Identify harmful germs
- Destroy bacteria and viruses
- Produce antibodies
- Remember past infections
When germs enter the body, WBCs attack and destroy them.
What Are Germs?
Germs are microorganisms that cause diseases.
Types of Germs
- Bacteria
- Viruses
- Fungi
- Protozoa
Types of Immunity
There are two main types of immunity:
1. Natural immunity1. Natural Immunity
Natural immunity is the immunity a person is born with.
Characteristics
- Present from birth
- Protects against many common infections
- Depends on genetics and overall health
Example: Natural barriers like skin and stomach acid.
2. Acquired Immunity
Acquired immunity develops during life after exposure to germs or vaccines.
Types of Acquired Immunity
a) Active Immunity
- Developed after infection or vaccination
- Long-lasting protection
b) Passive Immunity
- Antibodies received from another person
- Short-term protection
Example: Antibodies passed from mother to baby.
What Is Vaccination?
Vaccination is the process of introducing a vaccine into the body to stimulate immunity.
A vaccine contains:
- Weak germs
- Dead germs
- Parts of germs
Vaccines do not cause disease, but help the body prepare for it.
Vaccination Process (Step-by-Step)
1. Vaccine is given to the bodyHow Vaccines Protect Us
- Train the immune system
- Prepare the body for future infections
- Reduce severity of diseases
- Prevent spread of infections
Importance of Vaccination
Vaccination:
- Prevents serious diseases
- Saves millions of lives
- Protects children and adults
- Reduces disease spread
- Helps eliminate diseases
Diseases Prevented by Vaccination
- Polio
- Measles
- Tuberculosis
- Tetanus
- Diphtheria
- Hepatitis
Immunity and Community Protection
When many people are vaccinated:
- Disease spread reduces
- Vulnerable people are protected
- Community becomes healthier
This is called herd immunity.
Common Myths About Vaccination (Brief)
- Vaccines do not weaken immunity
- Vaccines are safe when taken properly
- Side effects are usually mild
Difference Between Natural and Acquired Immunity
| Feature | Natural Immunity | Acquired Immunity |
|---|---|---|
| Present at birth | Yes | No |
| Developed later | No | Yes |
| Requires exposure | No | Yes |
| Example | Skin barrier | Vaccination |
How to Keep the Immune System Strong
- Eat nutritious food
- Get vaccinated
- Exercise regularly
- Get enough sleep
- Maintain hygiene
FAQs – Immunity and Vaccination
1. What is immunity?
The ability of the body to fight diseases.
2. Which cells fight germs?
White blood cells.
3. What is vaccination?
A method to build immunity using vaccines.
4. Do vaccines cause disease?
No, they only stimulate immunity.
5. What are antibodies?
Proteins that destroy germs.
6. What is natural immunity?
Immunity present from birth.
7. What is acquired immunity?
Immunity developed during life.
8. Why is vaccination important?
It prevents serious diseases.
9. What is herd immunity?
Protection of community due to widespread vaccination.
10. Can vaccination save lives?
Yes, it saves millions of lives every year.
