1. Diseases
Unit 5

2. By Definition Infectious disease Communicable disease
Caused by an agent that has invaded the body.
Communicable disease
Can be spread or passed
Non-infectious disease
Occurring from within the body, heredity, lifestyle
Non-communicable disease
Cannot be passed on
Pathogen
Any agent that causes disease

3. Types of Pathogens Bacteria (including toxins) Rickettsia Viruses
Fungi
Protozoans
Parasites

4. Bacteria A single-celled microbe or organism
One of the widest spread of all living things
Three Basic Types (Identified by Shape)
Bacilli = rod shaped
Cocci = spherical shaped. Long chains are streptococcus and clusters(grapes) are staphylococcus.
Spirillia = twisted or spiral shaped

5. Bacteria continued…
Resident Bacteria – live on the human body to help protect you from infection
Mouth, skin, intestines
More than 300 in your mouth
Some bacteria give off poisons while others enter and damage cells.
Examples: Tuberculosis, tetanus, sinus infections

6. Toxins Bacteria that produces poisons
Food Poisoning: effect depends on type and amount ingested leads to upset stomach, loss of respiration, and death.
Tetanus: a toxin found in the ground that enters through a wound or injury.
Bacteria cells split at such a rate that one cell not attacked in 15 ½ hours turns into 4.3 billion

7. Rickettsia Pathogens that grow inside living cells
Cause typhus, Rocky Mountain Spotted Fever

8. Viruses Smallest pathogen known to man
Made of genetic material and a protein coat
Takes over the living cell by release of nucleic acid, force cells to make new viruses
Spread rapidly and attack specific cells(Rabies=brain cells; HIV=T cells)
Examples: colds, mumps, flu, measles, HIV, AIDS, and severe acute respiratory disease(SARS)

9. Fungi
Single or multi-celled organisms that absorbs and uses nutrients of living or dead organisms.
Feeds off of plant, animal, human tissue
Live on skin, in lungs
Cause ringworm, jock itch, thrush, athlete’s foot

10. Protozoans
Single-celled organisms that produce toxins that cause a disease.
Larger and more complex internally than bacteria
Cause: Malaria, African Sleeping Sickness, and Amebic Dysentery

11. Parasites
Animal parasites get their energy and nutrients by feeding on other living things
Helminth
Tapeworms
Flatworms
Pinworms
Hookworms
Flukes
Head lice
Found in undercooked meat. Infect digestive tract, muscle tissue and blood. Poor hygiene.

12. Immunity
Active Immunity: when you have had the disease, you build antibodies.
Passive Immunity: Is passed from mother to baby during development or from transplants
Vaccines: Lead to active immunity by injecting a weakened or dead form of the disease.
Antibiotic Resistance: a condition in which bacteria can no longer be killed by a particular antibiotic.

13. Spreading Disease Close contact Direct contact
Sneeze, cough
Direct contact
touching
Contact with a vector(animal, insect)
Mosquito, dog
Contact with a fomite(object)
Food, water

14. D, D, D, Defense Major Defenses
Mechanical: dead cells, skins, mucous membranes
Chemical: resident bacteria, tears, gastric juices
Biological: the release of chemicals by the immune system.
White blood cells called neutrophils eat bacteria
Monocytes from the bone marrow eat bacteria also.

15. More Defense
Affected body cells release INTERFERON, a protective protein.
Fever is formed when the body can’t rid itself of internal heat. Fever weakens and kills some pathogens.
Some bacteria carry pyrogens(poison) that cause fever.

16. Common Bacterial Diseases
Meningitis
Inflammation of the membranes covering the brain and spinal chord.
May also be caused by viruses or sometimes by fungi or parasites
Spread my contact with saliva or mucus from infected person
Severe headache, fever, stiff neck sensitive to light, nausea
Can be treated by antibiotics if bacterial and caught early.
Tetanus
Lockjaw, affects the nervous system and causes painful, uncontrolled muscle spasms
Clostridium tetani, spores found in soil, enters body through wounds/cuts.
Treated with antibiotics, tetanus shot(every 10yrs)

17. Bacterial Diseases Salmonellosis Strep Throat
Infection of the digestive system from eating contaminated foods.
Headache, cramps, diarrhea, nausea, vomiting
OTC meds for symptoms, sometimes antibiotics
Cook foods thoroughly, wash hands
Strep Throat
Sore throat, fever, yellow or white specks on tonsils
Spread through contact with infected person
Take antibiotics

18. Bacterial Diseases Sinus Infections
Headache, tenderness of the sinuses, thick and greenish mucus, feeling of pressure in the head
Spread through contact with infected persons, allergens such as cigarette smoke or air pollutants
Treat with antibiotics

19. Viral Infections Influenza Virus Cold Mumps Flu
Headache, sore muscles, sore throat, fever, fatigue, cough
Spread by contact with infected person
Vaccinations; however, new ones developed each season b/c of new strains developed
Get plenty of rest and fluids
Cold
Scratchy, sore throat; sneezing and runny nose; cough
Wash hands, avoid infected people, get rest and fluids, treat symptoms
Mumps
Pain and swelling of glands in throat, fever, headache
Spread by contact with infected airborne droplets and personal contact
Vaccinations
Rest and plenty of fluids

20. Viral Infections Measles Mononucleosis
Rash covering body, fatigue, runny nose, cough, slight fever, small white dots in mouth
Spread by contact with infected person
Vaccination
Mononucleosis
Fever, swollen lymph nodes, sore throat, weakness
Avoid drinking or eating after others

21. Viral Infections Hepatitis
Inflammation of the liver, jaundice, fever, darkening of the urine
Spread by contact with bodily fluids of infected person and by eating/drinking infected food or water
Types A, B, C
A- vaccine, washing hands regularly
B- vaccine to prevent, but cannot once infected
B & C- life threatening, no cure

22. Fungal Infections Athlete’s foot Jock itch Ringworm
Skin becomes itchy and red and lesions may appear.
Keep clothing dry and practice good hygiene
OTC meds will kill the fungus

23. Protozoan Infections Often found in water and soil
About 20,000 kinds of protozoa, but only small number cause disease
Amebic dysentery: inflammation of intestine caused by an ameba causing nausea, diarrhea.
Malaria
Plasmodium
Passed by mosquitoes
Approx one million people die each year
Fever, chills, headache, fatigue, nausea
Can be prevented and treated with antimalarial drugs.

24. Parasitic Infections Inside body On the body Hookworms Flukes Pinworms
Tapeworms
On the body
Lice
Leeches
Ticks
Fleas

25. Lifestyle Diseases Lifestyle Disease Controllable Risk Factors
Diseases that are caused partly by unhealthy behaviors and partly by other factors.
Controllable Risk Factors
Diet and body weight
Daily levels of physical activity
Level of sun exposure
Smoking and alcohol abuse
Uncontrollable Risk Factors
Age
Gender
Ethnicity
Heredity

26. Cardiovascular Disease
A disease or disorder that results from progressive damage to the heart and blood vessels
The leading cause of death in the US
Stroke
High Blood Pressure
Heart Attack
Atherosclerosis

27. Stroke
Sudden attacks of weakness or paralysis that occur when blood flow to an area of the brain is interrupted.
Blood clot lodges in artery and cells begin to die due to loss of circulation or hole forms in a blood vessel and blood leaks into the brain
160,000 deaths each year
Warning Signs
Numbness or weakness in face, arm or leg
Trouble seeing in one or both eyes
Sudden dizziness or loss of coordination
Sudden, severe headache with no known cause

28. High Blood Pressure Hypertension, the silent killer
Blood pressure is the force that blood exerts against the inside walls of a blood vessel. Too high=extra strain on the walls and the heart.
Will cause the heart to weaken or fail

29. Heart Attack
The damage and loss of function of an area of the heart muscle.
About 1/3 are fatal
Blood clot gets stuck in one of the coronary arteries and stops blood flow to the heart. Heart cells die from lack of oxygen.
Warning Signs
Pressure, squeezing, or pain in center of chest
Pain spreading to shoulders, neck, arms
Chest discomfort with lightheadedness, fainting, sweating, nausea, shortness of breath

30. Atherosclerosis
The disease characterized by the buildup of fatty materials on the inside walls of the arteries.
Reduces or stops blood flow to parts of the body
Deposits break free and release clots into the bloodstream
May result in heart attack or stroke

31. Detection Check blood pressure Electrocardiogram Ultrasound
Normal falls between 80/50 and 130/85
140/90 is considered high
Electrocardiogram
EKG, measures electrical activity of heart to detect damage or irregular heart beat
Ultrasound
Angiography
Inject dye into coronary arteries to look for blockages

32. Treatment and Prevention
Diet and exercise
Medicine
Surgery
Angioplasty
Pacemakers
Transplants
Prevention
Cut down on fat and salt intake
Maintain healthy weight
Don’t smoke
Exercise
Check BP and cholesterol
Relax