Diseases are caused by invading pathogens (aka: stuff that gets you sick) that affect, change or stop the functions of the organ systems.

these pathogens overtake the immune system, often growing faster than the Immune System can destroy them. There are 3 main types of diseases: bacterial, viral, and parasitic.

Bacteria are prokaryotic organisms that are able to grow very quickly if they have 3 things… 1. Food source—favorites are sugars and proteins 2. Moisture 3. Warm environment..all 3 things found inside the human body.

Most bacteria are actually harmless or helpful to the human body.

Harmful Bacteria cause illness when they release toxic chemicals into the body as they feed. These toxins can poison body cells, or stop important nervous functions.

Common symptoms of a bacteria infection are… 1. Fever 2. Upset stomach/vomiting, ect

1. Swelling of lymph nodes—small organs located in the neck and armpits that help clean the bloodstream. 2. Red, Sore areas of infection or Or pus-filled parts.

1. Botulism (aka: food poisoning) --Caused by eating spoiled canned food. --these bacteria release a neurotoxin that shuts down the nerves, muscles and respiratory system.

-usually fatal if untreated. Symptoms include fever, blurred vision, difficult to swallow/breathe, droopy eyelids and weak muscles.

--treated by… 1. Antitoxins/antidotes 2. Antibiotics 3. Stomach pump/inducing vomiting to remove spoiled food from the stomach.

2. Tuberculosis (TB) --very contagious—breathed in from infected people. --these bacteria release toxins that destroy the respiratory, circulatory, and nervous system.

--very fatal, even with treatment. --symptoms include fever, coughing, loss of appetite, sudden, severe weight loss..

TB is treated with multiple antibiotics, given daily over a 9 month period, and plenty of fresh air.

3. Meningitis --can also be caused by fungi, viruses, or protist cells. --the disease attacks the meninges(aka: dura)—a skin layer that protects the brain and nerves.

--The disease causes the meninges to swell, damaging the brain and spinal cord. The disease eventually destroys brain and nerve cells, and stops blood flow to the arms and legs.

Symptoms of meningitis include...

--very fatal disease, survivors often have permeant brain damage/paralysis and loss of fingers/hands/feet/toes. -spread from infected people, common in college-age students.

--viral diseases are the most common type in living things. --Viruses cause illness as they destroy cells during their reproduction cycle (aka: Lytic Cycle)

--Different viruses attack different type of cells. --most common signs of a viral infection include coughing/stuffed nose, aches/pains, low energy, vomiting and chills.

Recovery from viral infections happen only when the body fights it off on its own. Feeding the body plenty of vitamins, especially Vitamin C and Z (zinc), getting rest helps speed up recovery. Vaccines help prevent many viral infections.

1. AIDS/HIV (Acquired Immune Deficiency Syndrome) --spread from infected people ONLY through blood contact, or unprotected sex with a infected person, or childbirth.

Symptoms of HIV/AIDS include… --fever lasting over a month --swollen lymph nodes over a month --constant, and long-lasting illnesses

--The AIDS/HIV attacks the body’s White Blood Cells, eventually destroying the Immune System. --No working vaccine, cure—death is caused by another infection that the body cannot fight off.

2. Bronchitis/pneumonia --can be caused by bacteria too. --cold-causing viruses get into the bronchial tubes, (bronchitis) or the alveoli (pneumonia) causing them to create mucus to flush the viruses out.

Symptoms of bronchitis /pneumonia include… --constant, unhelpful cough, lasting weeks --shortness in breath --chest pain --low body temperature

--typically treated with rest and plenty of good foods/liquids. --Bronchitis is rarely fatal, but without treatment, pneumonia can be fatal.

3. Gastroenteritis (aka: norovirus/stomach flu) --caused by eating or drinking food with the virus, or breathed in--it’s extremely contagious.

Gastroenteritis attacks the cells in the stomach and intestines, and symptoms include… --Violent, constant vomiting --diarrhea --feeling dizzy --cannot keep food/drink down

Rarely fatal, recovery can only happen after the stomach/intestines have been completely emptied— do not feed this illness! --outbreaks of the norovirus have closed schools.

4. Mononucleosis (aka: Mono, the kissing disease) --spread by oral contact with infected saliva, through kissing, or sharing food and drink. Infects children and teens.

--nearly everyone gets this virus, but people with strong immunity do not develop symptoms. --symptoms include… --swollen glands/tonsils --high fever -- pus-filled sores in mouth/throat --tired, weak feeling

--very rarely fatal—recovery occurs with plenty of rest and good food, but may take weeks or a month.