Disease Notes

Non-Infectious (Body Disorders or Non Communicable) – No pathogens

Caused: poor nutrition, lifestyle (smoking, not exercising, overeating, too much sun, stress), genetics, old age

Examples: Diabetes, arthritis, cardiovascular, Parkinson’s, senile, Alzheimer’s, cancers (benign- not spreading uncontrollably or malignant – cancerous & spreading)

Treatment- Vary by disease- some don’t have treatment – some treatments just slow the process- some manage the disorder

Cancer- surgery, radiation therapy, chemotherapy, immunotherapy

Autoimmune- Could be non-infectious or infectious (rheumatoid arthritis, Lupus, or AIDS) Body attacks its own cells

Infectious(Communicable)- Pathogens (micro organisms) can be passed from one person to another and cause disease

Pathogens- Microscopic organisms that cause disease

- Bacteria- Good: Cheese, Bad: Produce poisons to harm cells or attack cells and prevent them growing. Treat with medication (antibiotics) (ex: Food poisoning, gonorrhea, pneumonia, strep throat, tuberculosis)

- Fungi- Good: Mushrooms, Bad: produce enzymes that digest body cells (ex: athletes foot & ringworm)

- Protozoa- Protist that causes Maleria lives in and destroys liver & blood cells. Ameba causes diarrhea or amebic dysentery.

- Parasites- Feed on the other animals, worms

- Viruses- Enters & destroys cells to reproduce. No cure, body’s immune system must kill (ex: Cold, influenza, chicken pox, hepatitis, herpes, & AIDS)

Spread-

Person to person- Infected people carry pathogens in saliva, mucus or excrement. Can be transmitted by direct or indirect contact. Sneezing or coughing spreads infection through the air. Through sexual contact called sexually transmitted diseases.

Foods & drinking water -Salmonella bacteria lives on farm animals or cholera spread in drinking water contaminated by sewage

Animal bites -Malaria carried by mosquito. Lymes disease carried by tick. Dog/mammals carry rabies

Blood from infected person (hepatitis & AIDS)

Stages- Infection à Incubation à Recovery

↓ ↑

Pathogen Multiples à Illness

↑↓

RelapseàDeath

Defense/Prevention-

1^st line of defense (barriers)

Skin is both physical & chemical (sweat destroys bacteria) barrier.

Body secretions help block entrance into mouth(saliva & stomach acid), nose (mucus & cilia trap and sweep out) Tears wash away & destroy.

2^nd line of defense: Immune system

Non specific:

Inflammatory response: Occurs at wound site. Increase blood flow & area becomes red, swollen, and warm & starts to clot. Prevent from entering & heat helps to kill

Fever: many pathogens can’t survive high temperatures

Specific:

Macrophages- surround & digest & send out interleukin 1 to raise body temp & activate T cells

Lymphocytes (Helper T or B) T clear out dead cells & gather proteins to recognize pathogen & send interleukin 2 to B. B receive message & multiply & change to plasma that makes antibodies (proteins to recognize and tag)

Antibodies-(& complements) stay attached to pathogen- macrophages engulf. Stay in body to recognize pathogen. Act like keys

Help with defense:

Vaccinations: contains dead or weakened pathogens so the body can recognize the disease and make antibodies for it without getting sick. (measles, mumps, polio, diphtheria, & whooping cough)

Active Immunity- prevents disease but can’t cure (vaccine or pathogens)

Passive Immunity- antibodies from a sick person – only last a short time (diphtheria, tetanus, measles, rabies)

Medicines: antibiotics treat bacterial infections (not viral) kill the bacteria & prevent it from reproducing (Penicillin)