PROPHYLACTIC TREATMENT OF HYDROPHOBIA 581 



absorb the moisture), the diminution of virulence being propor- 

 tional to the length of time during which the cords were kept. 

 Accordingly, by taking a series of such spinal cords kept for 

 various periods of time, he was supplied with a series of vaccines 

 of different strengths. Pasteur at once applied himself to find 

 whether the comparatively long period of incubation in man could 

 not be taken advantage of to " vaccinate " him against the 

 disease before its gravest manifestation took place. The 

 following is the record of the first case thus treated. The technique 

 was to rub up in a little sterile bouillon a small piece of the 

 oord used, and inject it under the skin by means of a hypodermic 

 syringe. The first injection was made with a very attenuated 

 virus, i.e. a cord fourteen days old. In subsequent injections 

 the strength of the virus was gradually increased, as shown in 

 the table : 



July 7, 1885, J) A.M., cord of June 23, i.e. 14 days old. 



The patient never manifested the slightest symptom of hydro- 

 phobia. Other similarly favourable results followed ; and this 

 prophylactic treatment of the disease quickly gained the con- 

 fidence of the scientific world, which it still retains. 



An important modification in the method which further experience led 

 Pasteur to make was in the treatment of serious cases, such as multiple 

 bites from wolves, extensive bites about the head, especially in children, 

 cases which come under treatment at a late period of the incuhation 

 stage, and cases where the wounds have not cicatrised. In such cases 

 the stages of the treatment are condensed. Thus on the first day, say 

 at 11 A.M. and 4 P.M. and 9 P.M., cords of 12, 10, and 8 days respectively 

 are used ; on the second day, cords of 6, 4, and 2 days ; on the third 

 lay, cords of 1 day ; on the fourth day, cords of 8, 6, and 4 days ; on 

 the fifth, cords of 3 and 2 days ; on the sixth, cords of 1 day ; and so on 

 for ten days. In each case the average dose is about 2 c.c. of the emulsion. 



The details of the prophylactic treatment with regard to 

 dosage and virulence of material used vary in different Pasteur 

 institutes. The most important modification which has within 



