1. Preventing Communicable Diseases

2. Physical and Chemical Barriers
Skin- first line of defense
Few pathogens can get through the first layers skin cells
Tears and saliva- contain enzymes that destroy pathogens
Mucous membranes- produce mucous, a sticky substance that traps pathogens and helps dispose of them
Line mouth, nose, bronchial tubes, and others

4. Cilia- hair-like projections that line parts of the respiratory system
Sweep mucus and pathogens to the throat, where they can be swallowed or coughed out
Gastric Juice- destroys pathogens in the stomach

7. Immune System
Network of cells, tissues, organs, and chemicals that fight of pathogens
The Inflammatory Response
A reaction to tissue damage caused by injury or infection
Blood vessels around the injury or infection expand to allow more blood to the area

8. Fluid and cells from the blood stream move into the area

9. Swelling and pain results from the pressure of fluid on nerves
Phagocyte- white blood cell that attacks invading pathogens
Engulf pathogens and kill them with chemicals
Pus forms- dead white blood cells and damaged tissue
Specific defenses are activated

11. Specific Defenses
Specific defenses react to an invasion as a result of the body’s ability to recognize certain pathogens and destroy them.
Immune response= immunity= the state of being protected against a particular disease.
Your immune system has a “memory”

12. Memory cells circulate in blood stream and lymphatic system
Specific types of white blood cells, T cells and B cells, have been activated by antigens and become memory cells
Antigen- found on the surfaces of pathogens and toxins
Capable of triggering an immune response
Memory cells circulate in blood stream and lymphatic system

13. If measles enter again antibodies will attack immediately
If memories cells recognize the antigens of a former invader certain white blood cells, B cells, make cells to stop it
Antibodies- acts against a specific antigen, destroys or blocks pathogens from entering cells
Killer T cells- attack and destroy infected body cells
Ex: If you have had the measles or a vaccination your body remembers antigens
If measles enter again antibodies will attack immediately

14. Active Immunity
Occurs when your body develops antibodies for a specific pathogen
Natural active immunity- when you are exposed to invading pathogens
Artificial active immunity- antibodies develop in response to a vaccine
Vaccine- dead or weakened pathogens that are injected into the body to stimulate the immune response

16. Active immunity can last a lifetime for some pathogens
Other pathogens require repeating immunizations (vaccine)

17. Passive Immunity Receiving antibodies from another person or animal
Passed from mother to child during pregnancy and nursing
From injection of antibodies that were produced by animal are human that is immune to disease.
This type of immunity is short lived

18. Care of the Immune System
Eat balanced diet
Drink water
Get plenty of rest
Fatigue reduces the effective ness of immune system
Manage stress
Avoid sharing
Keep immunizations up to date
Avoid sexual contact- some STDs destroy immune system

19. Four types of Vaccines
Live-virus- from pathogens made in lab under conditions to cause the pathogen to lose some disease causing property
Measles, mumps, rubella and chicken pox
Killed virus- from dead pathogens
Still stimulated immune response
Flu, hepatitis A, rabies, and cholera

20. Toxoids- inactivated toxins from pathogens are used
Tetanus
New and second-generation-new types in development by scientist

21. Immunizations for All
A person who is vaccinated not only protects themselves but those around them
You will not spread the disease to other
Keep immunization up to date
Tetanus
Diphtheria
Pertussis (whooping cough)
Measles, mumps, and rubella (MMR)
Chicken pox
Human Papillomavirus HPV
Most high schools and colleges require some of these