Visit our foundation to give a gift.
View Locations Near Me
Main Campus – Hartford
Connecticut Children’s – Waterbury
Urgent Care – Farmington
Specialty Care Center – Danbury
Connecticut Children’s Surgery Center at Farmington
Specialty Care Center – Fairfield
Search All Locations
Find a doctor
Find A Doctor
Request an Appointment
Amenities and Services
Who’s Who on Care Team
Getting Ready for Surgery
What to Expect—Picture Stories
Understanding the Different Fees
Estimate of Financial Liability
Pay a Bill
United Technologies Family Resource Center
Family Advisory Council
Legal Advocacy: Benefits, Education, Housing
Electronic Health Records
Share Your Story
Pay a Bill
Login to MyChart
Clinical Support Services Referrals
About the Network
Join the Network
Graduate Medical Education
Continuing Medical Education
MOC/Practice Quality Improvement
Educating Practices in the Community (EPIC)
Learning & Performance
Meet our Physician Relations Team
Request Medical Records
Join our Referring Provider Advisory Board
View our Physician Callback Standards
Read & Subscribe to Medical News
Register for Email Updates
Update Your Practice Information
Refer a Patient
Find and Print Health Info
Health Information For Teens
Whether you’re stomping through the showers in your bare feet after gym class or touching the bathroom doorknob, you’re being exposed to germs. Fortunately for most of us, the immune system is constantly on call to do battle with bugs that could put us out of commission.
The immune system is the body’s defense against infections. The immune (pronounced: ih-MYOON) system attacks germs and helps keep us healthy.
Many cells and organs work together to protect the body. White blood cells, also called leukocytes (pronounced: LOO-kuh-sytes), play an important role in the immune system.
Some types of white blood cells, called phagocytes (pronounced: FAH-guh-sytes), chew up invading organisms. Others, called lymphocytes (pronounced: LIM-fuh-sytes), help the body remember the invaders and destroy them.
One type of phagocyte is the neutrophil (pronounced: NOO-truh-fil), which fights bacteria. When someone might have bacterial infection, doctors can order a blood test to see if it caused the body to have lots of neutrophils. Other types of phagocytes do their own jobs to make sure that the body responds to invaders.
The two kinds of lymphocytes are B lymphocytes and T lymphocytes. Lymphocytes start out in the bone marrow and either stay there and mature into B cells, or go to the thymus gland to mature into T cells. B lymphocytes are like the body’s military intelligence system — they find their targets and send defenses to lock onto them. T cells are like the soldiers — they destroy the invaders that the intelligence system finds.
When the body senses foreign substances (called antigens), the immune system works to recognize the antigens and get rid of them.
B lymphocytes are triggered to make antibodies. These specialized proteins lock onto specific antigens. The antibodies stay in a person’s body. That way, if the immune system encounters that antigen again, the antibodies are ready to do their job. That’s why someone who gets sick with a disease, like chickenpox, usually won’t get sick from it again.
This is also how immunizations (vaccines) prevent some diseases. An immunization introduces the body to an antigen in a way that doesn’t make someone sick. But it does let the body make antibodies that will protect the person from future attack by the germ.
Although antibodies can recognize an antigen and lock onto it, they can’t destroy it without help. That’s the job of the T cells. They destroy antigens tagged by antibodies or cells that are infected or somehow changed. (Some T cells are actually called “killer cells.”) T cells also help signal other cells (like phagocytes) to do their jobs.
Antibodies also can:
These specialized cells and parts of the immune system offer the body protection against disease. This protection is called immunity.
Humans have three types of immunity — innate, adaptive, and passive:
The immune system needs help from vaccines. Getting all your recommended vaccines on time can help keep you as healthy as possible. So can washing your hands well and often to avoid infection, eating right, getting plenty of sleep and exercise, and going for regular medical checkups.
Your eyes itch, your nose is running, you’re sneezing, and you’re covered in hives. The enemy known as allergies has struck again.
Eczema is a common skin problem among teens. If you have eczema, read this article to find out more about it and how you can deal with the skin stress.
Doctors are diagnosing more and more people with food allergies. Knowing what to expect and how to deal with food allergies can make a big difference in preventing serious illness.
Lupus is a disease that affects the immune system. Learn how lupus is treated, signs and symptoms, how to support a friend who has it, and more.
Did you know that the most important thing you can do to keep from getting sick is to wash your hands? If you don’t wash your hands frequently, you can pick up germs from other sources and then infect yourself.
The lymphatic system is an extensive drainage network thatÂ helps keep bodily fluid levels in balance and defends the body against infections.
Learn about juvenile idiopathic arthritis, a specific kind of arthritis that usually occurs in kids and teens younger than 17.
Germs are tiny organisms that can cause disease – and they’re so small that they can creep into your system without you noticing. Find out how to protect yourself.
Nearly everybody gets diarrhea every once in a while, and it’s usually caused by gastrointestinal infections. It’s nothing to be embarrassed about. Read this article to learn more.
Note: All information is for educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor.
© 1995-2020 KidsHealth®. All rights reserved.
Images provided by The Nemours Foundation, iStock, Getty Images, Veer, Shutterstock, and Clipart.com.