26G BACTERIA AND DISEASE 



Septic Sore Throat. — This disease is characterized by very 

 severe sore throat and fever, and is often followed by heart or 

 kidney trouble. This is another milk-borne disease, which is 

 caused by a streptococ'cus. The disease is probably given to cows 

 by humans who may be carriers. Thus the cow may harbor the 

 germ for several weeks and persons drinking unpasteurized milk 

 from such a cow may take the disease. Several severe epidemics 

 have been recorded, in Baltimore, Chicago, and other cities, but 

 the worst was an outbreak of 2000 cases in Boston, in 1911. 



Tetanus. — The bacterium causing tet'anus is another toxin- 

 forming germ. It lives in dust and dirt and is often found on the 

 skin. It enters the body through cuts or bruises. It seems to 

 thrive best in less oxygen than is found in the air. It is therefore 

 important not to use court-plaster over wounds which such germs 

 may have entered. The low death rate from tetanus in the World 

 War was due largely to the fact that wounds were washed with 

 powerful antiseptics and anti-tetanus serum was administered as 

 soon as possible after the wounded were reached. 



Other Diseases Caused by Bacteria. — A group of bacteria 

 which cause pneumonia, erysipelas, and other common infections 

 besides septic sore throat are the so-called streptococci. Other 

 coccus forms, the staphylococci (staf-i-l6-k6k'sl) , are responsible for 

 boils and abscesses. A micrococcus causes one of the pernicious 

 venereal diseases, which produce terrible results. Other forms of 

 micrococci probably cause cerebro-spinal meningitis (men-in-ji'tis), 

 formerly a fatal disease of the spinal cord but now often treated 

 successfully with serums. Anthrax, or splenic fever, Malta fever, 

 whooping cough, bubonic plague, gas gangrene, one form of 

 dysentery, cholera, and many other diseases are definitely associ- 

 ated with specific forms of bacteria. Scarlet fever has recently 

 been added to the list of diseases caused by cocci. Other dis- 

 eases, as malaria, yellow fever, African sleeping sickness, and 

 probably smallpox and measles, are due to the attack of one- 

 celled animal parasites (which will be described in Chapter XXIV) . 



Summary. — This chapter has shown us that bacteria are found 

 almost everywhere and can easily be studied in the laboratory. 

 Fortunately, comparatively few of the many forms cause disease. 

 Pathogenic or disease-causing bacteria, however, cause a large 



