FUTURE OF OPSONINS AND VACCINES. So 



v.-ux Miit' on the point or from the tube is well rubbed in, the serum 

 is allowed to dry and a dry sterile dressing is put on. 



The reaction produced by successful vaccination usually ap- 

 pears after about three days. Locally, there is at first a papule, 

 wh idi becomes a pustule on the eighth or tenth day. About the 

 end of the second week the vesicle changes to a scab, which comes 

 off and leaves a scar. Constitutional symptoms usually appear 

 about the third day and last until the end of the first week after 

 vaccination. When there is infection, cellulitis and sloughing fol- 

 low; these conditions are treated as any other infection, but usually 

 ought not occur. 



The duration of immunity varies and is uncertain. The 

 longest time that immunity can be certainly relied upon is two 

 years. The rule for vaccination which is generally adopted and 

 advised consists in vaccination within the first or second year, 

 certainly before entering school, re-vaccination within the tenth to 

 fifteenth year and after that whenever there is an epidemic of 

 small-pox or possibility of exposure to the disease. 



The efficiency of vaccination against small-pox cannot be 

 doubted. The mortality in vaccinated individuals is between five 

 and eight per cent, while in the unvaccinated thirty-five to forty 

 per cent of the cases terminate fatally. The disease thus is milder 

 in vaccinated than in unvaccinated individuals. Moreover fewer 

 cases of small-pox occur in the vaccinated than in those not vac- 

 cinated against small-pox. 



FUTURE OF OPSONINS AND VACCINES. 



As the method of determining the opsonic index stands today 

 it is of questionable value in diagnosis and treatment of bacterial 

 diseases. Opsonins may play no part in immunity; on the other 

 hand, they may be quite important, and we be lacking in compre- 

 hension of their value and their determination. Further efforts 

 should be made to study them. 



The treatment of the bacterial diseases by killed cultures 

 ought not be cast aside because of the unreliability of the present 

 method of determining the opsonic index, inasmuch as opsonins 

 are not the only immunizing substances produced by the injection 



