[CHAPTER XX]
TRANSMISSION OF DISEASE THROUGH THE AIR
Disease germs in the air
We take germs into our bodies with the air that we breathe. Since we cannot stop breathing and live, we must see to it that the air we breathe is kept pure.
Fig. 47. (a) Prevalence of germs in air of thickly populated districts. (b) Prevalence of germs in air of sparsely populated districts.
There are always more germs in the air of places in which people live closely crowded together than where there are only a few people. This is proved by Figure 47, which shows that many more germs were found on a culture plate exposed in the downtown part of New York City than on another plate exposed far uptown, where there are not so many people. Remember, however, that all germs are not disease germs.
How we may keep disease germs out of the air:
How do the disease germs get into the air? When one sneezes, a spray of droplets is thrown into the air. If the person sneezing has the grip, these droplets contain the germs that cause grip. Whenever a person with consumption coughs, he sprays droplets which contain the germs that cause consumption.
(1) When coughing or sneezing