1. Infectious Diseases

2. Myth There isn’t much a person can do to avoid spreading or catching a cold or the flu.
Fact About 80% of infectious diseases are spread by hand contact. Washing your hands with soap and water is a simple and effective way to prevent the spread of colds and the flu.
Do you think most teens wash their hands as much as they should? What do you think are some ways to encourage more frequent hand washing?

3. Causes of Communicable Diseases
Communicable diseases, also know as infectious diseases are caused by organisms or viruses that enter and multiply within the human body. These can also be known as pathogens.
Pathogens.
Viruses
Fungi
Bacteria
Protozoa / Parasite

4. Bacteria Bacteria - single-celled microorganisms that live everywhere:
air, soil, food, and in and on the bodies of plants and animals, including you.
Common Types of Bacteria Infections:
Strep throat
Lyme Disease
Pertussis (whopping cough)
Tuberculosis
Salmonella

5. Strep Throat
“Strep” is short for Streptococcus, the bacterium that causes the disease.
Strep bacteria, which are usually found in the nose and throat, can be spread by contact with mucus from an infected person.
Symptoms include
sore throat
swollen lymph nodes on the sides of the neck
headache
fever

6. Lyme Disease
Humans can become infected with the bacteria that cause Lyme disease when they are bitten by an infected tick.
Symptoms of Lyme disease include
a red rash at the site of the tick bite
fever
chills
body aches
The best way to protect yourself from Lyme disease is by avoiding tick bites.

7. Bacterial Meningitis
An infection of the fluid in the spinal cord and the fluid that surrounds the brain is called meningitis.
Symptoms of meningitis include high fever, headache, vomiting, and a stiff neck.
There are two types of meningitis—one is caused by bacteria, the other by a virus.

8. Tuberculosis
A highly contagious bacterial infection of the lungs is tuberculosis (too bur kyuh LOH sis), or TB.
It is transmitted when droplets from an infected person’s cough or sneeze are inhaled.
Symptoms, which include fatigue, weight loss, a mild fever, and a constant cough, may not show up for many years after the initial infection.

9. Fungi
Organisms such as yeasts, molds, and mushrooms are known as fungi.
Fungi grow best in warm, dark, moist areas.

10. Treating Bacterial Diseases
An antibiotic is a drug that inhibits or kills bacteria.
Using antibiotics exactly as they are prescribed is very important to prevent bacteria from developing resistance to the medicine.
Antibiotic resistance can result if you don’t finish your prescription and some of the bacterial pathogens in your body survive.

11. Viruses
The smallest pathogens are viruses that multiply after entering a living cell.
Common Types of Viral Infections:
Common Cold
Chickenpox
Mononucleosis
Influenza
Measles – can come back (just like chickenpox, but way worse)
Rabies

12. The Common Cold
The common cold is really a group of symptoms that is caused by a number of different viruses.
One or two days after exposure to a cold virus, people develop
sneezing
sore throats
runny noses
coughing
chest congestion
fever
headaches
muscle aches
Colds spread when a person touches a contaminated object or inhales droplets from a sneeze or a cough.

13. Influenza
The flu, or influenza, is a common viral infection of the upper respiratory system.
Influenza is spread by airborne droplets and contact with contaminated objects.
High fever, sore throat, headache, and a cough are typical symptoms of the flu.

14. The Stages of the Flu

15. Pneumonia
In people who are elderly, or who have heart disease or breathing problems, flu may develop into pneumonia (noo MOHN yuh), a serious infection of the lungs.
Many people die each year from pneumonia, which can be caused by viruses, bacteria, or even fungi.

16. Hepatitis
A group of viruses that infect the liver can cause hepatitis (hep uh TY tis), or inflammation of the liver.
Symptoms of hepatitis include
fever
nausea
pain in the abdomen
jaundice (JAWN dis), or yellowing of the skin.
Hepatitis A is transmitted in human wastes and in contaminated water and food.
Hepatitis B can be transmitted in blood, during sexual contact, or during tattooing or body piercing.
Hepatitis C can be transmitted in blood, during sexual contact, or during tattooing or body piercing.

17. Treating Viral Diseases
There is no particular medicine that can cure a viral infection.
The best treatments for viral infections are rest, a well-balanced diet, and plenty of fluids.
Many over-the-counter medicines can treat the symptoms of viral infections.

18. Protozoans
Larger and more complex than bacteria are known as protozoans.
Protozoans have the ability to move through fluids in search of food.
Common Types of Protozoans:
Malaria
Tape Worm

19. Pathogens
Viruses
Fungi
Bacteria
Protozoa / Parasite

20. How Pathogens Are Spread
Pathogens can spread through contact with
an infected person
an infected animal
contaminated objects
contaminated food/water
contaminated soil
contaminated air
The pathogens can then enter the body through breaks in the skin or through the moist linings of the eyes, ears, nose, mouth, or other openings.

21. Infected People
Many infectious diseases are spread through some form of contact with a person who has the disease.
The contact may be direct physical contact.
Infectious diseases can also spread through indirect contact.

22. Infected Animals
Some infectious diseases are transmitted to humans through the bites of animals.

23. Contaminated Objects
Some pathogens can survive for a period of time outside a person’s body.
These pathogens can be spread from person to person on objects such as
doorknobs
eating utensils
towels
needles used for body piercings and tattoos

24. Contaminated Food, Soil, or Water
Some pathogens are naturally present in food and soil.
Sometimes water and food become contaminated with pathogens from infected people.

25. Contaminated Air
Sneezing, coughing, or your environment

27. Passive immunity is passed from mother to baby.
Passive Immunity - acquired by receiving antibodies from a source other than one’s own immune system. It is temporary, not lifelong.
Passive immunity is passed from mother to baby.

28. Active Immunity – results from either having the disease or from receiving the vaccine. The injection is called an immunization and the substance is called a vaccine.
Vaccines contain small amounts of dead or modified pathogens.

30. When to Seek Medical Care
an extremely sore throat, earache, vomiting, diarrhea, or a temperature of 101°F that lasts more than two days
mucus from your nose or throat that is thick and yellowish green
difficulty breathing, or severe pain anywhere
a cut, scrape, or sore that does not seem to be healing as it should
an illness that lasts longer than usual (2 weeks)

31. Preventing Infectious Diseases
Wash your hands several times a day, especially before eating and after using the bathroom
Do not share items that can transfer pathogens, such as towels, eating utensils, cups, or hairbrushes.
Cook and store foods properly. Meats should be cooked thoroughly. Hot foods should be kept hot, and cold foods should be kept cold.
Stay home when you are not feeling well.
Avoid close contact with people who are ill.
Learn to manage stress in healthful ways, and get at least eight hours of sleep each night.
Eat well-balanced meals, and do not skip meals. Exercise regularly, at least three or more times a week
Avoid unhealthful substances, such as tobacco, alcohol, and illegal drugs.