118 IMMUNOLOGY 



month intervals. Two months after either of these immunization 

 programs the Schick test should be done as a routine in order to see 

 that immunity has actually developed. In the infant who has 

 actually received the immunization at that period of life and a 

 Schick test found negative, the Schick test should be repeated once 

 yearly until the age of five years to see that the immiuiity is being 

 held. It is not rare for a child from two to five years to lose im- 

 munity, especially if he has had only one dose of alum toxoid, or 

 two doses of regular toxoid. A check each year is of protective 

 value. 



(4) "Active immunization against tetanus may be obtained by 

 the use of tetanus toxoid given at two-month intervals and may be 

 combined with the diphtheria toxoid at the first and third doses of 

 that toxoid. It may be prepared separately or combined with the 

 diphtheria toxoid. It is well to use two such doses of toxoid 

 following a passive immunization against tetanus Avith the tetanus 

 antitoxin in which case, however, immunity is probably more 

 complete. Therefore, whenever a protective dose of tetanus anti- 

 toxin is given in cases of an accident the individual should be given 

 a dose of tetanus toxoid within two weeks and follow this two 

 months later with a second tetanus toxoid. 



(5) ''Scarlet fever active immunization at the second or third 

 year of age is advisable. Most children are susceptible at that age. 

 One objection to the Dick toxin active immunization has been the 

 reactions accompanying the rapidly increasing repeated doses 

 recommended by Dick. This objection can be overcome by using 

 half of the ampule at the injection, thus making ten doses rather 

 than the regular five. There is practically no reaction from this 

 attenuated dose. It is well to do a Dick test first and if negative 

 it will be unnecessary to go ahead with immunization. The Dick 

 test should be repeated two months after the series of injections 

 so that one can see that there is a reversal of the previous positive 

 test. 



(6) "Measles Immune Globulin will produce passive immunity if 

 injected within a day or two after exposure to measles. This 

 should be done in frail, delicate, young children. But a modifica- 

 tion of the disease may be obtained by one or two doses of this 

 preparation given from six to eight days after a known exposure. 



