CHAPTER VII. 

 BACTERIA CAUSING ACUTE INFECTIONS. 



THE BACILLUS OF TETANUS. 



TETANUS, or lockjaw, as it is more commonly 

 called, has existed for many centuries, but the micro- 

 organism causing the infection was not discovered 

 until 1885, when Nicolaier, a German bacteriologist, 

 was successful in producing the disease in animals by 

 injecting them with small amounts of soil, 

 rphoi- The organism is a bacillus of large size, which 



forms spores readily. It grows on the ordinary cul- 

 ture media, but only when no oxygen is present. The 

 spores are located at one end of the bacillus, and cause 

 a swelling which gives it much the same shape as a 

 drumstick. The spores are very resistant to harmful 

 influences. They will survive dry heat of 80 C. for 

 an hour and 5 per cent, carbolic acid solution for 

 twelve to fifteen hours. Away from sunlight the 

 spores may live for years. 



Its natural home is the soil, especially where it 

 has been cultivated and manured. This is due to the 

 fact that tetanus bacilli are present in the intestines of 

 some animals. In the United States the soil in the 

 Hudson Valley and on Long Island seems particularly 

 infectious. 



Infection generally occurs by the contamination 

 (70) 



