GO IN DEPTH

Antibiotic Attack

What You Need

 
Antibiotic Attack

Purpose

To help students understand how the human body may not work as well or at all if harmful germs are able to get inside it and how antibiotics can help someone get better.


Context

Almost all students at this age will have been given antibiotics at one time or another. Certainly, all students will have been sick, and will have some thoughts about getting sick and getting well.

Students may have a general sense of what makes them sick. For example, they may know that if germs are able to get inside one's body, they may keep it from working properly. For defense against germs, the human body has tears, saliva, skin, some blood cells, and stomach secretions. A healthy body can fight most germs that do get inside. However, there are some germs that interfere with the body's defenses. (The Science NetLinks lesson Germs and the Body is a good introduction to germs.)

But what are germs? And how do antibiotics fight them? Elementary school students may have these ideas about germs: germs are microorganisms causing illness; every illness is caused by germs; all diseases are caused by the same kind of germ; any infection in the body necessarily makes it ill; when medicine is administered, healing takes place immediately. (Benchmarks for Science Literacy, p. 345.)

This lesson starts with a discussion that will help clarify how germs cause disease. The discussion leads to the lesson’s basic idea: antibiotics kill bacteria or prevent them from reproducing.

At this level, students also are starting to understand the human body as a system of interdependent parts and to perceive that something may not work as well (or at all) if a part of it is missing, broken, worn out, mismatched, or misconnected. (Benchmarks for Scientific Literacy, p. 264.) You can bring this idea into the discussion by pointing out that the bacterial infection may be concentrated in one area of the body, but it affects the entire system. In fact, the body is such a complex system that a beneficial antibiotic may cause side effects that are uncomfortable and even harmful. When prescribing antibiotics, doctors must be careful to balance their positive and negative effects.

This line of discussion is a good introduction to Antibiotic Attack, an online interactive that simulates the activity of antibiotics in a game-like setting. In this activity, the player can "zap" germs with a strong antibiotic, but each zap raises the severity of the side effects. Too much of a strong antibiotic will send the patient to the hospital—but so will too little.

In the follow-up discussion, you can talk more about the idea of “resistant” bacteria mentioned in the activity’s “Learn More” section. As a wrap-up, you present ideas for further discussion, and present a classroom activity in which each student plays the role of a doctor trying to identify the bacterial agent infecting a patient.

Read More

Motivation

Start with a general discussion of bacteria and how they cause disease. Ask students:

  • How many of you have ever had: cavities, an ear infection, a sinus infection, pneumonia, strep throat, lyme disease, or some other disease?
    • (You may want to list these options on the board and record students' answers.)
  • How many other kinds of disease do you know about?
    • (Answers may vary.)
  • What makes people sick?
    • (Germs can make people sick.)
  • What are germs?
    • (They are microorganisms, viruses, and bacteria.)

Tell students to create pictures of germs. (The ones who volunteered stories about being sick could draw the germs that made them sick; others could draw the germs that cause the diseases you just listed.)

Now explore with students the definition of a germ. The dictionary says that a germ is a microorganism that causes disease. Bacteria, viruses, and fungi are all types of microorganisms. An “infection” is when a germ invades your body and starts multiplying. This can make you sick in four different ways:

  1. The number of germs in one area of your body can cause swelling.
  2. The germs can use up food that your body’s cells need.
  3. Germs can attack your body’s tissues directly, or produce poisons that harm them.
  4. Your body’s own defense mechanisms may fight the infection so strongly that it may make you feel worse.

Ask students:

  • Do you think all diseases are caused by the same kind of germ?
    • (It is to be hoped that students say “no.”)
  • How many different kinds of germs do you think there are?
    • (There are thousands, even millions. Student answers will vary.)
  • When you were sick, did your doctor give you an antibiotic? Did it help?
    • (Answers may vary.)
  • What is an antibiotic?
    • (It is a type of medicine that kills bacteria.)

Development

In this part of the lesson, students will continue to explore antibiotics in more detail. Begin by explaining to students that most ear infections, sinus infections, and strep throat are caused by bacteria. Antibiotics are designed to kill bacteria. Ask students:

  • Often, people who get ear infections or strep throat have high fevers. Why do you think a bacterial infection in one part of the body can affect the entire body that way?
    • (Answers may vary.)

Remind students that the human body is a system—a collection of interdependent parts. A bicycle is another kind of system—a collection of mechanical parts. Ask students:

  • Let’s say your bicycle gets a flat tire. The other tire isn’t affected; the brakes, the pedals, and the other parts are still OK. But can you ride the bicycle?
    • (No.)
  • Why?
    • (You want students to come around to the idea that what happens to one part of a system affects the entire system.)
  • Could the same thing happen with the human body? If something were to happen to one part of it, would that affect the entire body? Why?
    • (Yes, because the human body is a system. If one part were hurt by a bacterial infection, the whole body would suffer.)

The human body is a very complex system, with many interdependent parts. In fact, some of those parts are bacteria! Some kinds of bacteria help your body digest food and even protect you from other germs.

One problem with antibiotics is that they kill good bacteria in addition to bad bacteria. Another problem: your body has its own defenses against disease. When some antibiotics come in and attack bacteria, your body starts fighting the antibiotics—and that can make you feel even sicker. These problems that an antibiotic causes are called “side effects.”

Ask students:

  • If antibiotics kill bacteria, and bacteria are important parts of your system, doesn’t that make them too dangerous to take as medicine?
    • (Students may have a variety of answers. Most antibiotics that doctors prescribe only kill certain kinds of bacteria—the “bad” ones that make you sick. There are some stronger antibiotics that kill many kinds of bacteria. “Stronger” antibiotics have stronger side effects.)
  • How do you think a doctor decides what antibiotic to give you?
    • (The doctor tries to figure out what kind of bacteria you are infected with, and how strong an antibiotic you need.)

Now ask students to use the Antibiotic Attack student esheet to help them go to and play the Antibiotic Attack interactive activity. Have students read the directions on the esheet, which will lead them to the activity. Ask students to click the “How to Play” section and read the instructions.

Point out the tips and questions in Step 5 of the esheet, and suggest that students keep these in mind as they try the activity.

Students should answer these questions once they’ve done the activity:

  • How do you figure out which antibiotic to use?
    • (Answers may vary.)
  • Which is better: using an antibiotic that only kills one type of germ, or using a “strong” antibiotic that kills many kinds?
    • (Answers may vary.)
  • Why did you have to keep switching antibiotics to get rid of all the germs?
    • (Some antibiotics only killed certain germs; different antibiotics were needed to kill the other germs.)
  • With any patient, did you think you’d gotten all the germs, but couldn’t go on because one or two were still there, only hidden?
    • (Answers may vary.)
  • Did you use the strongest antibiotic? What happened?
    • (Answers may vary.)
  • Did you max out on side effects?
    • (Answers may vary.)

You can extend this discussion with these questions:

  • Which is better to use, a stronger antibiotic or a less strong antibiotic?
    • (Answers may vary.)
  • How is this different from real treatment using antibiotics?
    • (Answers may include: a doctor can't see what germs are causing diseases; they must figure this out by observing the patient’s symptoms; usually, an antibiotic is given as a pill or a shot, not “zapped” into different parts of the body; in real life, they don't zap you with shot after shot of antibiotic; in real life, there is less danger from side effects.)
  • In this game, which is more likely to get maxed out: the patient’s fever or the side effects?
    • (Answers may vary.)

You also can follow up on the issues raised in the activity’s “Learn More” section, about why a doctor might not prescribe the strongest antibiotic:

  • The strongest antibiotic might be the most expensive.
  • The strongest antibiotic might have more side effects.
  • Bacteria that survive the strong antibiotic might become resistant to that antibiotic—so the next time you get an infection, the strong antibiotic might be less effective.
Read More

Assessment

To assess student understanding of what you have covered in this lesson, ask them questions like these:

  • What does it mean when we say a type of bacterium is “resistant” to an antibiotic?
      (The antibiotic won’t kill that strain of bacterium.)
  • How would you know if you were infected with a resistant strain of a certain bacterium?
      (An antibiotic that worked for that type of infection before doesn’t work anymore.)
  • So how could it happen that an antibiotic that helped you once could not be as effective another time?
      (If the antibiotic kills all except a few resistant bacteria, and those multiply, the same antibiotic won’t work as well on the new infection.)
  • What do you think would happen if you took an antibiotic when you aren’t infected with the type of bacterium the antibiotic is designed to kill?
      (Answers could include: if you are sick, the antibiotic won’t help; the antibiotic’s side effects might make you sicker; the antibiotic might wipe out non-resistant bacteria, leaving the resistant bacteria to multiply, so that the next time you really need that antibiotic it won’t work.)

Medical experts make these recommendations for using antibiotics. Ask students to explain the recommendations based on their understanding of how antibiotics work:

  • Take only those antibiotics that are prescribed for you—don't take someone else's antibiotics, or antibiotics that you find around the house.
      (If you have an infection, you need an antibiotic that targets the specific bacteria that are infecting you.)
  • Don’t ask for a stronger antibiotic.
      (The stronger the antibiotic, the worse the side effects might be.)
  • When a doctor prescribes an antibiotic for you, take all of it as directed.
      (The idea is to kill all of the bacteria, and not leave any that might develop a resistance to the antibiotic.)
  • When you’re sick, rest. Don’t go back to your normal routine just because you think the antibiotic will handle the problem.
      (The antibiotic’s job is to help your body’s natural defenses heal you. If you don’t take it easy, the antibiotic won’t be able to do its part.)

Conduct the following activity using the Bacteria Zoo student sheet provided. Make as many copies of the sheets as are needed for you and the students. Keep one set for yourself and distribute the rest of the sets to the students.

Tell students how the activity will work:

  • The “Bacteria Zoo” sheets describe made-up strains of bacteria. The entry for each gives its name, tells you what symptoms you would see in someone infected with that bacterium, and gives you the name of an antibiotic that you should prescribe.
  • The students are to consider the case of a patient infected with one of these bacteria. In turn, each student can ask the teacher one “yes or no” question about the patient's symptoms (“Does the patient's hair stand straight up?” “Are the patient's knees blue?” etc.). If possible, write each of the patient’s actual symptoms on the board as soon as they are identified.
  • During his or her turn, each student has the opportunity to identify the infecting bacterium and prescribe an antibiotic to fight the infection. The first student to do so correctly (DURING his or her turn) wins the round.

Choose one of the bacteria types and start the activity, following the rules. After the students have identified the bacterium and prescribed the right antibiotic, you can start another round or stop the activity.


Extensions

These Science NetLinks lessons can help extend the learning in this lesson:

  • Systems of the Human Body would be a good way to help extend student thinking about the human body as a system.
  • Germs and the Body explores where germs exist, how they can get into and affect the body, and how the body defends itself against them.

To help students think more about the use of antibiotics, ask them these questions:

  • Have any of you ever had a cold, the flu, or athlete's foot? These diseases are NOT caused by bacteria. (The first two are caused by viruses, the third by a fungus.) Should you take antibiotics for any of these diseases?
  • Do you think people should take antibiotics every day, even if they’re not sick?
  • Some farmers that raise cattle and other food animals give the animals antibiotics every day to prevent infections. Those antibiotics can still be present in the food made from those animals. Why do you think some people are concerned about that?

 

Microbe Gallery has pictures of bacteria.


Did you find this resource helpful?

Lesson Details

Grades Themes Type Project 2061 Benchmarks
AAAS Thinkfinity