There are some diseases that humans can only catch once because after the initial infection, the body's immune system remembers how to fight the disease if exposed again. Examples include chickenpox. Other diseases like the common cold or strep throat can infect people many times because there are multiple variants of the disease, so the immune system may not recognize repeat infections. Still other diseases can be prevented altogether by vaccines, which expose the body to a harmless version of the disease, allowing it to develop protective antibodies before actual exposure.

1. DISEASES: ONCE OR NOT AT ALL

2. INDICATOR 4.4.11 Explain that there are some diseases that human beings can only catch once. Explain that there are many diseases that can be prevented by vaccinations so that people do not catch them even once. http://www.indianastandardsresources.org/files/sci/sci_4_4_11.pdf Information taken from IDOE website

3. DEFINITIONS Disease: a disordered or incorrectly functioning organ, part, structure, or system of the body resulting from the effect of genetic or developmental errors, infection, poisons, nutritional deficiency or imbalance, toxicity, or unfavorable environmental factors; illness; sickness; ailment . Vaccine: any preparation used as a preventive inoculation to confer immunity against a specific disease, usually employing an innocuous form of the disease agent, as killed or weakened bacteria or viruses, to stimulate antibody production.

4. DEFINITIONS CONTINUED Immune: protected from a disease or the like, as by inoculation. Epidemic: affecting many persons at the same time, and spreading from person to person in a locality where the disease is not permanently prevalent.

5. BACKGROUND INFORMATION A disease is is any disturbance in the normal functioning of the body that probably has a specific cause and identifiable symptoms. Some diseases have vaccines that help prepare the body to fight off the disease. However, some diseases are not vaccine preventable such as a common cold or strep throat because there are so many types it is impossible to prepare the body for each one. Other diseases like Chicken Pox are most commonly caught once because the body recognizes the disease and is able to protect itself if the disease comes back.

6. PRE – ACTIVITY / PREPARATION Draw three columns on your piece of paper, writing the following words in the top of each column: ■ caught once ■ caught lots ■ caught never

7. THIS IS WHAT YOUR PAPER SHOULD LOOK LIKE Caught Once Caught Lots Caught Never

8. ACTIVITY Think about times when you have been sick. After looking at the categories fill in each column? Which diseases do most people catch only once? (e.g., chicken pox) Which diseases can make you sick lots of times? (e.g., strep throat, common cold, pink eye) Which diseases have you heard of before, but never caught? (e.g., mumps, polio, rubella, scarlet fever)

9. 2. Why do some diseases only make you sick once, while you might catch others many times? Why are there diseases you may never catch? 3. Most humans only get sick once from diseases like chicken pox, because after they have had the disease, their bodies can recognize it and know how to fight it again. 4. Diseases like the common cold or an ear infection make humans sick lots of times because the diseases have more than one type .

10. 5. Your body may learn how to protect itself from strep throat, but you catch it again because there are many types of strep throat your body has not seen before. When your body does not know how to fight a disease, you get sick. 6. Have you ever been to the doctor to get a shot? Do you know why you had to get a shot? Some shots contain medicine, while others contain vaccines. 7. Scientists have made vaccines, which are treatments that help the body learn how to fight certain diseases.

11. 8. Discuss how you will most likely never get sick from the mumps or polio, because you have had vaccines to protect you against these diseases. 9. Look at the chart, Which diseases listed have vaccines? Write check marks next to each disease that has a vaccine. List of vaccine - preventable diseases from CDC website

12. ACTIVITY 2 Draw a time when you have had a disease. After drawing the picture think about what you have learned and write a description of your disease under the picture and say whether your disease has a vaccine, can be caught more than once, or is just a common cold.

13. ACTIVITY 3 Think about a time when you have gone to the doctor to get a shot. What were you feeling? After brainstorming, write a paragraph about your fear of needles and shots. You can also draw a picture of this experience.

14. ASSESSMENT Why do you only catch some diseases? Can you catch some diseases over and over again? How do you know? Is there a vaccine for the common cold? How do you know?

15. FOR MORE INFORMATION GO TO… http://www.bam.gov/sub_diseases/index.html Go to this website to learn more about particular diseases and what your body does to help fight them off! Also learn how scientist’s track diseases and much more!