In this chapter, you’ll learn about diseases like the flu and how diseases are
spread. You’ll also learn how to take simple precautions to control and prevent
the spread of diseases.CHAPTER 14: IMMUNITY
Inside your body there is a war going on. An army of B cells, T cells, natural
killer cells, and other parts of your immune system are on the defense. These
cells seek microbes to rip apart before any of them can give you a runny nose,
cough, or that dreaded feverish feeling.
The immune system is your body’s defense mechanism: Its “soldiers” sur-
round, neutralize, and destroy foreign invaders before they can do harm. In this
chapter you’ll learn about your immune system and how it gives you daily pro-
tection against invading microbes.CHAPTER 15: VACCINES AND DIAGNOSING DISEASES
Think about this: Each year millions of people pay their doctor to inject them
with the flu virus. On the surface that may not make sense, but after reading this
chapter you’ll find that it makes perfect sense because this injection is actually
a vaccination against the flu.
Avaccine prevents you from catching a certain disease because it has ele-
ments of that disease, triggering your body to create antibodies to the disease.
You’ll learn about vaccines and antibodies in this chapter.CHAPTER 16: ANTIMICROBIAL DRUGS
“Doc, give me a pill to knock out whatever is causing me to be sick!” All of us
say this whenever we come down with an illness. All we want is a magic pill that
makes us feel better. Sometimes that magic pill—or injection—contains a
microbe that seeks out and destroys pathogenic microbes, which are disease-
causing microbes.
In this chapter you’ll learn about antimicrobial drugs that are given as
chemotherapy to cure disease. These antimicrobial drugs contain microbes that
kill other microbes.xviii INTRODUCTION
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