germs get into the body, but sometimes it does not appear for three weeks after the person has been exposed to the disease. It is a very catching disease, and at the first symptoms of it children should be removed from school. As a general rule a child may be allowed to return to school in six weeks after

FIGS. 105 and 106. In schools where the sanitary drinking fountain cannot be installed, a covered water cooler and individual cups should be substituted for the old-fashioned open bucket and common drinking cups.

the beginning of the whoop, provided the hard coughing spells have ceased.

Influenza (grip). This is a very severe and a very catching disease. The germs of it are spread in the same ways that the germs of consumption, diphtheria, and pneumonia are spread. Much can be done to check the spread of influenza by keeping the germs from spreading from those who are sick with it. How much can be done in this way was

shown in a school in Norwalk, Connecticut. This school had in it about twelve hundred pupils, when an epidemic of grip occurred in the city. On the second floor all the children who took the disease were sent home and the rooms were disinfected each night. On this floor only twenty pupils were attacked. On the first floor no care was taken to prevent the spread of the germs, and two thirds of the children had the disease. Old people and sick people should be very carefully protected from influenza germs, and no one should expose himself to them when he can avoid doing so.

Colds. Colds may be caused by the pneumonia germ, the influenza germ, or by a number of other germs. They are very catching, and the germs are spread in all the ways that influenza or pneumonia germs are spread. A child who has a bad cold should not be in school, and any one with a cold should do all in his power to keep the germs from spreading to others.

Protecting ourselves from the germs of respiratory diseases. Do not stay about those who have diseases of the lungs and air passages unless it is necessary for you to be with them. Do not handle objects that they have handled, and do not use drinking cups that they have used. Do not put pencils and other articles into your mouth. Avoid breathing in dust as much as possible (page 53). Keep your hands away from your face, and

wash them well with soap and water before eating. These are some of the ways by which you can keep the germs that cause diseases of the air passages and lungs from getting into your body.

Good health a protection against certain germ diseases. We cannot depend on good health to keep us from taking diseases like smallpox, measles, typhoid fever, and other germ diseases that run a quick course. Good health is of great importance, however, in helping us to overcome the germs of lingering ailments like tuberculosis, catarrh, and bronchitis, and in protecting us from the slowgrowing races of germs that often set up their growth in the heart, kidneys, and other vital organs. In these diseases the body has plenty of time to build up its defenses, and among the best ways of protecting ourselves against them is to eat good food, to keep our teeth clean and sound, to take plenty of sleep and exercise, and to make sure that we have an abundance of fresh air. We ought to do everything in our power to avoid germs, but we ought also to keep our bodies strong for their battles with the germs. This we can do only by giving our bodies day by day the care that is necessary to keep them in health.

Clean teeth a protection against germ diseases. Suppose there are two boys in the same school; that one of these boys has clean, sound teeth, and that the other boy has the other kind of teeth. Suppose

that a bad cold, grip, pneumonia or diphtheria appears in the school, and that each boy gets a few of the germs into his mouth. Which boy will probably have the better digestion, the stronger body, and be more able to fight off the germs? In which mouth will the germs be likely to grow and multiply until the boy can no longer resist them? Which boy is more likely to carry the germs for some time in his mouth, to have them on his hands, and to leave them on anything he handles? These are questions which it will not be hard for you to decide.

Questions: 1. In what ways do the germs of diseases of the air passages and lungs get into the body? 2. How can one prevent the scattering of germs from a patient sick with pneumonia? 3. What is the cause of diphtheria? 4. Why should a family in which there is a case of diphtheria be quarantined? 5. How long should children who have whooping cough be kept out of school and away from well children? 6. How are the germs of influenza spread? 7. Does getting wet cause a cold? 8. What is the best way to avoid influenza and colds? 9. What is the greatest protection against diseases of the air passages and the lungs?

Suggestions and topics for development: The necessity for quarantining all cases of diphtheria and for sending home all children who have communicable diseases. Discuss any habits the children may have that allow the germs of respiratory diseases to spread from one pupil to another. Discourage the passing of objects from one pupil to another, and put away common drinking cups, wash basins, and towels. The teacher should realize that the public school is a great disseminator of germ diseases, and should strive to make it as safe as possible for the children who attend it.

MALARIA, SMALLPOX, AND OTHER GERM DISEASES

A

B

FIG. 107. The mosquito that carries malaria (A) has spots on its wings and stands up on its head when resting and biting. The common mosquito takes the position shown in B.

Malaria. The germ of malaria grows in the blood, and a person who is attacked by this disease may be troubled with it for months or years. One person cannot catch malaria from another person, but if a mosquito bites any one who has malaria germs in his blood, the mosquito gets the disease. Then, if the mosquito bites another person, it will leave the germs in the blood of the latter, and about a week later this person will have malaria. It was formerly thought that breathing air from swamps or drinking impure water caused malaria, but we now know that these ideas are not correct and that the disease is spread only by mosquitoes. In the next chapter we shall study how to destroy mosquitoes.