THE SERUM TREATMENT OF CHOLERA 823 



(a) In addition to Yersin's serum, which is prepared at the Pasteur Institute of 

 Paris by immunizing horses with dead and then with living cultures of pest bacilli, 

 other serums have been prepared. For example: 



(6) Kolle immunizes horses with intravenous injections of heat-killed cultures, 

 beginning with Y agar slant culture and doubling the dose each week until 15 cul- 

 tures are given at one time. The horses are bled fourteen days after the last dose 

 is given. 



(c) Lustig immunizes horses with pest-nucleoproteins, obtained by breaking 

 up the bacilli with 1 per cent, of potassium hydroxid and precipitating the proteins 

 with acetic acid. These are then suspended in sterile normal salt solution, as in the 

 preparation of Lustig's vaccine. 



(d) Terni-Bandi immunizes donkeys and sheep with aggressins obtained by 

 intraperitoneal injection of guinea-pigs with pest bacilli. 



(e) Markl immunizes horses with nitrates of old pest bouillon cultures. He 

 believes that the value of pest serum is largely dependent upon antitoxins. 



The serums are usually tested by injecting mice with lethal doses of pest culture 

 and decreasing doses of antiserum. The agglutinin content may also be measured. 

 According to Strong pest immune sera do not contain appreciable amounts of bac- 

 teriolysin, but are largely bacteriotropic in action. Whenever cultures are used in 

 immunization, the serum should always be cultured carefully and tested by animal 

 inoculation to guard against the possibility of living bacilli being present. 



i 



THE SERUM TREATMENT OF CHOLERA 



In some respects cholera would seem to oe due mainly to a toxin 

 elaborated by the bacilli in the intestinal tract of infected persons, 

 similar to the action of the toxin of the Kruse-Shiga type of dysentery 

 bacillus. Various attempts have been made to prepare an efficient 

 anticholera serum, but the only one that has yielded encouraging results 

 in experimental infections as well as in cholera of human beings is that 

 prepared by Kraus. This serum is prepared by immunizing horses 

 with a true toxin derived from a cholera-like vibrio isolated by Gottsch- 

 lich from the intestinal contents of pilgrims dying at El Tor from a dys- 

 entery or cholera-like infection. According to Kraus, this antiserum 

 is largely antitoxic, and serves to neutralize the toxin of true cholera 

 more effectively than does the antiserum resulting from immunization 

 with cholera cultures. A serum that is antitoxic and is obtained by pro- 

 longed immunization of horses by intravenous injections with dead cul- 

 tures of cholera, and later with living cultures, bacterial extracts, and 

 nitrates of old bouillon cultures conjointly, would seem to be a desider- 

 atum. 



Reports from Russia, where Kraus' and Kolle's serums have been 



employed, indicate that a reduction of about 10 to 20 per cent, in the 



mortality has been accomplished. Jegunoff's 1 method of administering 



the serum seems quite rational, and consists in making intravenous in- 



1 Wien. klin. Wchnschr., 1909, No. 24. 



