1. Preventing Communicable Diseases
Immune System – a network of cells, tissues, organs, and chemicals that fight pathogens.
First line of Defense- Physical and Chemical:
skin, mucous membranes, cilia
enzymes in tears, saliva, gastric juices

2. Inflammatory Response
A reaction to tissue damage caused by injury or infection. (hot, swollen, red, painful)
Release of Phagocytes – a white blood cell that attacks invading pathogens.
(Pus- a collection of dead white blood cells and damaged tissues)
Repair now begins at injured site.

3. Specific Defenses
When certain pathogens enter the body, the body’s immune response will recognize this pathogen and send out specific antigens- a substance that is capable of triggering an immune response.
This response is what we call immunity – the state of being protected against a certain disease.

4. Battling Specific Diseases
Lymphocyte- a specialized white blood cell that coordinates and performs many of the functions of specific immunity.
Two Types – “T” cells and “B” cells
(Helper “T” cells, Killer “T” cells, Suppressor “T” cells)
“B” cells produce antibodies – a protein that acts against a specific antigen.
An antibody will either mark a cell for destruction, destroy the antigen or block the virus from entering the body.

5. Memory Lymphocytes
Some “B” and “T” cells actually have a memory and circulate through the body looking for “bad” invaders who have been there before- if found, they begin the attack to prevent illnesses.
Active immunity- developed by your body
Artificial immunity- vaccine- a preparation of dead or weakened pathogens that are introduced into the body to stimulate an immune response.

6. Vaccines
Live virus vaccines – made from pathogens grown under special lab conditions to make them lose most of their disease causing properties. (measles, mumps, rubella, chicken pox)
Killed virus vaccines – inactivated pathogens. Still cause an immune response and antibodies are produced. (flu shots, polio, rabies, hepatitis A)
Toxoids – inactivated toxins from pathogens (tetanus, diptheria) used to stimulate production of antibodies.
New and second generation vaccines- developed by scientists using new technologies. (hepatitus B)

7. Common Communicable Diseases
Respiratory Infections (URI)
most caused by viruses and bacteria
avoid contact with infected people
smoking can reduce chances of fighting uri’s
Common Cold- runny nose, sneezing, sore throat, headache
Influenza- fever, chills, dry cough, joint pain, runny nose, sore throat, extreme fatigue
Pneumonia- an infection of the lungs in which the air sacs fill with pus and other liquids.

8. Strep Throat –(bacterial infection) sore throat, fever, enlarged lymph nodes. Treated with antibiotics.
Tuberculosis – (Bacterial) attacks the lungs. fatigue, coughing (blood), fever, night sweats, and weight loss.
Hepatitis- inflammation of the liver. Caused by chemicals and many other pathogens. No cure – but vaccines for A and B.
“A” – spread through contact with feces of an infected person. Not
washing hands properly before handling objects or food.
Jaundice- yellowing of skin and eyes.
“B” – more serious than “A”. Found in most bodily fluids, especially
blood. Transmitted sexually. Drug use, piercings, tatoos, etc.
“C” – most common, transmitted by direct contact with infected blood.

9. Other Common Diseases
Mononucleosis- virus, spread by direct contact sharing utensils, kissing- “kissing disease”. Chills, fever, sore throat, fatigue and swollen lymph nodes.
Measles – virus, spread by coughs, sneeze, close contact-highly contagious. Fever, red eyes, runny nose, cough, bumpy red rash.
Encephalitis – virus, transmitted by mosquitoes. Causing swelling of the brain. Headaches, fever, hallucinations, confusion, paralysis.
Meningitis – Virus or bacteria cause inflammation of the membranes that cover the brain. Fever, headache, nausea, vomiting, stiff neck