220 MODERN BIOLOGIC THERAPEUSIS 



ease. Children in families in which other mem- 

 bers are suffering from whooping-cough, or 

 those who are otherwise liable to exposure, 

 should be given immunizing doses of Pertussis 

 Vaccine, prepared from the Bordet bacillus. Dr. 

 E. Mather Sill, of New York, and others have 

 used this vaccine in a series of children in fami- 

 lies where other members were suffering from 

 whooping-cough and, although closely observed 

 for over two months, the children did not de- 

 velop the disease. 



Dosage Three doses of the vaccine are given 

 at intervals of seven days. The first dose con- 

 tains 25 million bacteria; the second 50 million 

 and the third 100 million. 



Reaction The clinical reaction after an in- 

 jection of the vaccine is similar to that following 

 the use of other prophylactic vaccines, although 

 the reaction is usually less marked. The local 

 reaction consists of redness, swelling, and slight 

 tenderness at the point of inoculation. Occas- 

 ionally there is a rise in temperature of one to 

 three degrees. The symptoms usually pass off 

 after 24 hours. 



Immunity It has been the general experience 

 of clinicians that, when a child is already in the 



