Chapter 13: Handwashing and Vaccines: Helping Your Guards

Every Guard Needs Helpers

Picture a castle on a hill. Guards stand at the gate, watch from the towers and patrol the walls. They are brave and clever, and they work day and night. But the people who live in the castle can help them too. The people can keep the gates clean, close the doors at night, and practice what to do if trouble ever comes. When everyone helps, the guards have a much easier job.

Your body is a little like that castle. In this book, you have met the guards that protect your lungs and breathing: the nose with its sticky mucus, the tonsils, the epiglottis, the escalator of tiny hairs, the cleaner cells in the alveoli and the germ fighters that travel in your blood. In the last chapter, you saw how your whole body fights back when germs manage to get inside.

Now it is your turn. There are simple things you can do every day that make your guards' work easier. Two of the most powerful are washing your hands with soap and water and getting vaccines that a doctor or nurse recommends. Neither of these is complicated. Neither needs special skills. Yet together, they have helped protect millions and millions of children around the world.

How Germs Hitch a Ride

Germs cannot walk, fly or swim on their own across a room. To travel from one person to another, germs need a ride. One of their favorite rides is a droplet. When someone coughs, sneezes, sings or even talks, tiny droplets of water spray out of the mouth and nose. Most of these droplets are too small to see. If that person is sick, the droplets can carry germs through the air to other people nearby.

Another favorite ride is your hands. Your hands are amazing tools. They open doors, hold pencils, pick up toys, pet animals, shake hands with friends and carry food to your mouth. All day long, your hands touch things that other people have touched too. Germs from those things can stick to your skin without your noticing at all.

Germs on your hands usually cannot hurt you while they stay on the outside of your skin. Healthy skin is a strong wall. The trouble begins when your hands carry the germs to the soft, wet places where germs can get into your body: your eyes, your nose and your mouth. People touch their faces many times every hour, often without even realizing it. Each touch is a chance for a germ to hop on board.

Here is a way to imagine it. Suppose you dipped your fingers in a little flour and then went about your day. Soon you would find white fingerprints on the table, on the door handle, on your cheek and on your friend's sleeve. Germs travel in a similar way, except that you cannot see them. That is why washing your hands is so useful: it takes the germs off your fingers before your fingers can spread them around.

You can also make droplets less likely to reach other people. When you cough or sneeze, cover your mouth and nose with a tissue, then throw the tissue away. If you do not have a tissue, cough or sneeze into the bend of your elbow, not into your hands. Your elbow does not open doors or hold snacks, so the germs are less likely to travel from there. After you cough, sneeze or blow your nose, wash your hands.

Soap and Water: A Simple Shield

Why does soap work so well? The answer is hidden in its shape. Soap is made of very tiny pieces, much too small to see, and each piece has two different ends. One end loves water and is drawn to it. The other end avoids water but loves oil and grease. Germs and dirt often stick to your skin in a thin, oily layer, which is why plain water alone does not wash them all away.

When you rub soap over wet hands, the oil-loving ends of the soap pieces push into the oily layer and grab on to it, along with the germs and dirt. The water-loving ends stick out into the water. Little by little, the soap pulls the oily layer apart and wraps tiny bundles of grease, dirt and germs inside a coat of soap. When you rinse, the water grabs the water-loving ends and carries the whole bundle down the drain.

Soap can also break apart some kinds of germs directly. Many viruses, including some that cause colds and flu, are wrapped in a thin, fatty outer coat. Soap can pull that coat apart, much as it pulls apart grease on a dirty plate. Without its coat, the virus can no longer cause an infection.

Rubbing is just as important as the soap itself. The rubbing helps the soap reach every corner of your hands and loosens the germs. Experts usually suggest scrubbing for at least about twenty seconds. That is about as long as humming a short song from beginning to end two times. It may feel longer than you expect the first few times, but it soon becomes a habit.

Here is one good way to wash your hands. Wet your hands with clean running water. Put on some soap and rub your palms together until you make a lather. Then rub the back of each hand, lace your fingers together to clean between them, scrub around each thumb, and rub your fingertips against your palms to clean under your nails. Rinse your hands well under running water. Finally, dry them with a clean towel or let them air dry, because germs spread more easily on wet hands.

When should you wash your hands? Some of the most important times are before you eat or help prepare food, after you use the toilet, after you blow your nose, cough or sneeze, after you play outside, and after you touch animals or their food. It is also a good idea to wash your hands when you come home from a busy place, and whenever your hands look or feel dirty. If soap and water are not available, a grown-up may have other ways to clean hands, but soap and water are the best everyday choice.

You do not need any special or fancy soap. Ordinary soap, whether it is a bar or a liquid, works very well when you use it with clean water and rub long enough. Warm water can feel more comfortable, but cool water cleans your hands just as well. What matters most is the soap, the scrubbing, the rinsing and the drying. A clean, dry towel is best, because a damp towel that many people share can collect germs of its own.

Handwashing does more than protect you. Every time you wash your hands, you remove germs that might otherwise reach your family, your classmates and your friends. One small habit, repeated by many people, makes a big difference. Health experts around the world agree that handwashing is one of the simplest and most effective ways to help stop germs from spreading.

The Immune System Never Forgets

To understand vaccines, it helps to remember something you learned in the last chapter. Your immune system, the body's whole team of germ fighters, has a memory. When your body meets a new germ for the first time, the immune system has to work out how to fight it. This can take several days, and during that time you might feel sick.

Part of the work is making antibodies. Antibodies are special proteins made by certain white blood cells. Each kind of antibody has a shape that fits one particular part of one particular germ, a bit like a puzzle piece that fits only one spot in the puzzle. When antibodies stick to a germ, they can stop the germ from getting into your cells, and they mark the germ so that other germ fighters can find it and destroy it.

After the fight is over, some of the white blood cells become memory cells. These memory cells remember the germ, sometimes for many years. If the same germ ever comes back, the memory cells recognize it at once. The body can then make the right antibodies quickly, often stopping the germ before you feel sick at all.

Think of how a team gets better at a game. The first time the players face a new opponent, they do not know the other team's tricks, but by the second match they remember what the other team did and are ready for it. Your immune system works in a similar way. But here is the problem: the first match against some germs can be very hard on the body. What if your guards could learn about a germ without having to fight the real thing first? That is exactly what a vaccine does.

Vaccines: Practice for Your Guards

A vaccine is a kind of practice for your immune system. A vaccine teaches your guards what a particular germ looks like, so that your body can be ready before the real germ ever arrives. It is like a fire drill at school. During a fire drill there is no real fire, but everyone practices what to do. If a real fire ever happened, everyone would already know the way out.

Another way to picture a vaccine is a wanted poster. In old stories, the people of a town would put up posters showing the face of a thief so that everyone could recognize the thief right away. A vaccine shows your immune system a kind of picture of a germ. Your guards study the picture, make antibodies that fit it and build memory cells. Then, if the real germ ever tries to sneak in, your guards spot it immediately.

Scientists have found several different ways to make that picture. Some vaccines contain germs that have been made inactive, so they cannot make you sick. Some contain germs that have been greatly weakened. Some contain only a small, harmless piece of a germ, such as a bit of its outer coat. Others give your cells instructions to make one harmless piece of a germ for a short time, so that your immune system can see it and learn. In every case, the goal is the same: to let your guards practice safely.

Here is what happens inside your body after a vaccine. First, guard cells near the place where the vaccine was given find the harmless germ picture and pick it up. These guard cells carry the picture to the nearest lymph nodes, the guard stations you read about in the last chapter. There, other white blood cells study the picture and start making antibodies that fit it. Over the next week or two, your body builds up its protection, and memory cells are formed to remember the picture for a long time.

Vaccines are carefully tested before they are given to people. Scientists and doctors study them in many people to make sure that they work and that they are safe. After a vaccine is in use, health experts keep watching to make sure it stays safe. This is one of the most carefully checked areas of medicine.

Vaccines have made a huge difference in the world. Some illnesses that once made many children very sick are now rare in many places, because so many people have been vaccinated. One serious disease, called smallpox, has been wiped out completely. Decades ago, people all over the world worked together to vaccinate against smallpox until the disease disappeared everywhere. It is one of the greatest achievements in the history of health.

Different vaccines protect against different germs, and doctors and nurses follow plans that show which vaccines are given and at what ages. Some vaccines are given when children are babies, some when they are older, and some, like a vaccine for the flu, may be offered again from time to time because the germs keep changing. Grown-ups can talk with a doctor or nurse about which vaccines are right for their child and when.

The Little Pinch and What Comes After

Many vaccines are given as a shot, also called an injection. A nurse or doctor uses a very thin needle to put the vaccine into a muscle, usually in the upper arm or the thigh. Some vaccines are given in other ways, such as drops in the mouth or a spray into the nose. It is perfectly normal to feel nervous about a shot. Lots of children feel that way, and lots of grown-ups do too.

Most people say that a shot feels like a quick pinch or a sharp poke that is over in a moment. Some things can help. You can hold a grown-up's hand, look at a picture on the wall, squeeze a soft toy, or breathe out slowly while the nurse gives the shot. Remember the breathing pump from an earlier chapter: long, slow breaths out can help your body feel calmer. It is also fine to tell the nurse that you feel scared. Nurses help nervous children every day and know many ways to make it easier.

After a vaccine, your arm may feel a little sore, red or swollen where the needle went in. Some children feel tired, a bit grumpy or slightly warm for a day or so. These feelings are usually mild and go away on their own. They are often signs that your immune system is busy studying the wanted poster and getting ready. A grown-up should talk to a doctor or nurse about any reaction that worries them.

Asking questions is always a good idea. You might want to know what a vaccine is for, or how long it will take, or whether it will hurt. You can ask your grown-up, or you can ask the nurse or doctor yourself. Understanding what is happening often makes it feel less scary. And when it is over, you can feel proud that you have given your guards a powerful lesson.

Protecting Each Other

Vaccines and handwashing protect you. But they also do something bigger. They protect the people around you, including people you may never meet.

Germs that spread from person to person need a chain of people to travel along. A germ jumps from one person to the next, then to the next, like a spark jumping from one dry leaf to another. When many people in a community are protected, the germ keeps landing on people whose guards are ready for it. The chain breaks, and the germ has a much harder time spreading. This is often called community protection.

Community protection matters most for people who cannot fully protect themselves. Some babies are too young to have had all their vaccines yet. Some people have bodies whose immune systems do not work as strongly, because of an illness or a treatment they need. Some older people find it harder to fight off germs. When the people around them are protected, these more delicate people are protected too.

You usually cannot tell just by looking at someone whether that person's guards are strong or weak. A friend's baby brother, a classmate's grandmother, or the person standing next to you in a line might be one of the people who most need protecting. That is one more reason why everyday habits are so helpful. You do not have to know who needs protecting. By looking after your own hands and your own health, you help to keep everyone safer.

Think of a group of friends holding umbrellas close together in the rain. Each umbrella keeps one person dry, but together the umbrellas make a roof that also shelters the small child standing in the middle without an umbrella. Each person who washes their hands and stays up to date with the vaccines recommended for them helps hold up that roof.

So the next time you scrub your hands for twenty seconds, cover a sneeze with your elbow, or get a vaccine, you can remember that you are doing two jobs at once. You are helping your own guards, and you are being a guard for others. In the next chapter, you will discover another way to look after your lungs for your whole life: by keeping the air you breathe as clean as possible.

Key Words

Germ: A tiny living thing, or a virus, that can cause illness if it gets into the body. Most germs are far too small to see.

Droplets: Tiny drops of water that fly out of the nose and mouth when people cough, sneeze or talk. They can carry germs from one person to another.

Soap: A cleaner made of tiny pieces with one end that loves water and one end that loves oil, so it can lift away grease, dirt and germs.

Handwashing: Scrubbing all parts of your hands with soap and water for about twenty seconds, then rinsing and drying them, to remove germs.

Antibody: A special protein made by certain white blood cells. Each kind fits one particular germ and helps the body stop that germ.

Memory cells: White blood cells that remember a germ, so the body can recognize and fight the same germ quickly in the future.

Vaccine: A safe way to teach the immune system what a germ looks like, so the body is ready to fight that germ before it causes illness.

Injection: Another word for a shot, when a doctor or nurse uses a thin needle to put a vaccine or medicine into the body.

Community protection: The protection that comes when many people in a group are protected against a germ, so the germ has fewer ways to spread to anyone.