VACCINE OR OPSONIC THERAPY 105 



is followed by general and local disturbances similar 

 to those following typhoid vaccination. There is some 

 redness and swelling at the site of injection, fever, 

 nausea, and general malaise, all of which pass off in 

 from twenty-four to thirty-six hours. 



Effects. The immunity conferred is not as great as in 

 typhoid and appears to disappear in about six months. 

 The vaccination should be repeated in ten to fifteen 

 days to make the protection more certain. It is believed 

 that a greater protection is afforded by combining the 

 vaccine with the administration of Yersin's antitoxin. 



Typhoid Vaccine. This is prepared by cultivating a 

 strain of typhoid bacilli of diminished virulence. The 

 culture is killed by heat, a small amount of antiseptic 

 added to prevent contamination in handling, and the 

 culture diluted so that each cubic centimeter represents 

 1,000,000 dead germs. This is the usual dose, though it 

 may be reduced one-half and repeated in ten or twelve 

 days. 



Administration. The dose is injected subcutaneously 

 in the arm or abdomen, under the usual antiseptic pre- 

 cautions. Following the injection there is some local 

 reaction, accompanied by redness, swelling, and some 

 pain and swelling in the regional lymphatic glands. 

 There are also some constitutional disturbances, varying 

 from a slight indisposition to chills and a temperature 

 of 100 to 100.2 F., with general aching headache, 

 nausea, and diarrhea. They all disappear, however, 



