936 HUMAN SERUM FROM CONVALESCENT CASES 



development of varicella re-exposed three children of this same group of whom none 

 developed the disease, although this represented their third exposure forty days fol- 

 lowing the single injection of convalescents' serum. 



They were able to make some other interesting observations on the possible 

 length of time during which convalescents' serum was protective. A group of six 

 children was accidentally re-exposed to a child with varicella thirty-two days after the 

 injection. Later, four of this same group had a third accidental exposure fifty days 

 after injection. None of them, however, contracted the disease in spite of three 

 exposures, the last being fifty days after their one injection of convalescents' serum. 

 The protection from the serum from convalescent varicella is apparently longer than 

 that from measles convalescents. 



The amount of serum used in fifty-four patients was between 4 and 5 cc; one 

 patient received 10 cc; four received 6 cc; seven received 3 cc; two received 2 cc. 

 All but nine of the patients had received the serum within from one to three days after 

 exposure. Of these nine patients, seven had received serum within five days, one 

 within six days, and one within seven days. The three patients developing the disease 

 all had received 4 cc of serum, two of these not until five days after exposure. It is 

 problematical whether more serum injected at a shorter interval after exposure would 

 have protected these patients. 



The serum used was obtained within from ten to fourteen days after the onset of 

 varicella from adults who had negative Wassermann reactions. It was preserved by 

 the addition of 10 per cent by volume of 0.7 per cent sodium chloride solution con- 

 taining I per cent phenol, and it was kept in sealed glass tubes in an icebox. Serum 

 as old as eleven months was apparently successful in protection. The injections were 

 given deep into the anterior thigh muscles, and in no case was there a local reaction. 

 One patient developed definite serum sickness with fever and urticaria nine days after 

 the injection of varicella convalescents' serum. Three weeks previously he had been 

 given scarlet fever convalescents' serum intramuscularly. 



The percentage developing varicella in the total group of sixty-eight patients was 

 4.4. Excluding thirteen patients, who were fifteen years of age or over, and eleven 

 patients who were six months of age or younger, the percentage developing the disease 

 in the remaining forty-four was 6.8. 



PROPHYLACTIC USE OF CONVALESCENT SERUM FROM PERSONS HAVING HAD MUMPS 



In view of these considerations it is interesting to consider what may be accom- 

 plished in preventing mumps, or epidemic parotitis, especially in institutions in which 

 a large number of cases arise from time to time. Mumps is still to be ranked among 

 the highly contagious infective diseases of unknown etiology, the specific causative 

 microbic agent not having been discovered. The disease is, however, one in which one 

 attack yields protection that is general and persistent. The question arises, there- 

 fore, whether the blood of persons who have recovered from one attack of the disease 

 does not contain immunizing and protective principles which can be employed in the 

 protection of other exposed persons. Hess in 191 5 utilized the blood of convalescents 

 in an attempt to control an epidemic of mumps in the Home for Hebrew Infants, 

 which for the second time in two years was visited by a severe epidemic The epidemic 



