BACILLUS ICTEROIDES AND BACILLUS CHOLERA SUIS.-A PRELIM- INARY NOTE. BY WALTER REED, M.D., SURGEON UNITED STATES ARMY, JAMES CARROLL, M.D., AND ACTING ASSISTANT-SURGEON UNITED STATES ARMY. FllOM THE MEDICAL NEWS, April 29, 1899. [Reprinted from The Medical News, Apr. 29, 1899. ] BACILLUS ICTEROIDES AND BACILLUS CHOLER/E SUIS.—A PR ELI MI.NARY NOTE. By WALTER REED, M.D., Surgeon United States Army, AND JAMES CARROLL, M.D., Acting Assistant-Surgeon United States Army. In the course of a comparative study of bacillus x (Sternberg) and bacillus icteroides (Sanarelli) which has engaged our attention as opportunity would per- mit during the past eighteen months, we have had occasion to observe the effect produced by the in- travenous injection in dogs of other micro-organisms, such as the bacillus coli communis and the bacillus cholerae suis. Without entering into details in this preliminary note we may state that the same clinical symptoms, viz., vomiting, increased action of the bowels, and profound prostration, which are pro- duced in dogs by the intravenous injection of B. ic- teroides, are also brought about by a like inoculation of the hog-cholera bacillus. When death occurs, the stomach contains a considerable quantiy of fluid blood and extensive hemorrhagic lesions are present in the small intestine. We have not found fatty degeneration of the liver, since our dogs, few in number, injected with the hog-cholera bacillus, have died too early for this change to occur. We have also failed to discover any fatty degeneration in the liver of dogs that have died within a few days after the intravenous injection-of--D.- -irtcroid.es: 4dtis- 2 change has only been met with in two instances, when the animals had survived until the ninth day after inoculation with B. icteroides. In neither of these cases, however, was the degree of fatty degen- eration at afl comparable with that present in the human liver in yellow fever. In addition to the experiments upon dogs, we have compared the course of the infection and the lesions produced in guinea-pigs and rabbits inoculated with small quantities of B. icteroides and B. cholerae suis, and have been much impressed with the similarity of the results obtained. The same cyclical course of the infection described by Sanarelli for guinea- pigs inoculated with B. icteroides is seen in these animals when injected with like quantities of B. cholerae suis. The greater susceptibility and shorter course of the infection in rabbits applies equally to both micro-organisms. Theobald Smith has called attention to the extreme susceptibility of these ani- mals to inoculation with minute quantities of the hog-cholera bacillus.1 We have succeeded in killing rabbits with -nrsTroirir c-c- icteroides injected subcutaneously. The lesions produced in rabbits and guinea-pigs inoculated with B. icteroides and the hog-cholera bacillus are practically the same, the most constant change consisting of multiple necroses in the liver. Sanarelli does not appear to have made any mention of this most striking lesion. We have found these punctate necroses of the liver especially prominent in guinea-pigs that have survived the in- oculation more than five days. Observations have shown that pigeons are not 1 Bulletin No. 6, U. S, Department of Agriculture, 1894. 3 very susceptible to inoculation with the hog cholera bacillus. We have also found these birds to be tol- erably resistant to infection with B. icteroides. A fatal result has been produced by injecting 3 c.c. of a bouillon-culture into the breast muscle. Hemor- rhage, swelling and extensive necrosis of the muscle are present, under these circumstances, as has been described by Welch and Clement, for the hog-chol- cra bacillus.1 We desire also to record in this preliminary note that bacillus icteroides, when fed to young hogs, produces an acute infection which may be followed by a fatal result, and that the chief lesion is confined to the large intestine. This lesion consists of an in- flammation of the mucous membrane accompanied by fibrinous exudate, together with numerous small and large superficial ulcerations affecting the colon and cecum. These ulcerated areas are covered by an abundant, thick, bile-stained exudate. The “cork-lining” appearance mentioned by Smith would apply to the description of the necrosed intesti- nal mucosa. A portion of the viscera of a young hog that had been fed with 25 c.c. of a 24-hour bouil- lon-culture of Sanarelli’s bacillus and which had died on the sixth day of the disease was fed to a second animal. The latter after exhibiting symp- toms of sickness, such as fever, shiverings and loss of appetite, for a few days appeared to have fully re- covered from the inoculation. It was killed on the 18th day. At autopsy numerous ulcers in various stages of cicatrization were found in the large intestine. 1 “Hog Cholera and Swine Plague,” Welch and Clement, 1894. 4 In another animal which died on the twelfth day after being fed 15 c.c of a twenty-four-hour bouillon culture of B. icteroides we found erosions upon the tongue, a well marked diphtheritic inflammation of the lining membrane of the esophagus from pharynx to stomach, involving the latter; eroded ulcers with hemorrhagic bases upon the gastric mucosa; super- ficial erosions and circumscribed ulcers, bearing a yellowish slough, in the small intestine and cecum; and, in addition, there were several hundred dis- tinctly raised, neoplasmic, button-like elevations of about the size of a small split pea beneath the mu- cous membrane of the large bowel. A few of these showed a small, superficial, centrally situated spot of necrosis. The mucous membrane of the gall-bladder was the seat of a well marked necrotic inflammation, and there was also inflammation and erosion of the mucous membrane of the prepuce, which was dis- tended with a dirty, yellowish-colored fluid. As regards the morphologic and biologic characters of B. icteroides and B. cholerse suis we have been unable to observe differences other than may be met with in varieties of the same species. Both are small, quite non-liquefying bacilli whose slow rate of growth is the same in bouillon and in gelatin; likewise on agar, potato, and in litmus milk the growth presents the same appearances. Milk is not coagulated by either of these bacilli. The action of B. icteroides and B. cholerge suis upon the three sugars has been the same in our hands. Both ferment glucose. If the bouillon is free from muscle glucose no fermentation takes place in lactose or saccharose bouillon. Exceptionally we 5 have recorded a very slight fermentation of saccharose with both organisms. Both of these bacilli, when cultivated in Dunham’s solution, give a faint mdol reaction. We desire further to record the marked agglutina- tive reaction exhibited toward the hog-cholera bacillus by the serum of an animal immunized with B. icteroides. As long ago as May, 1898, we had observed that the blood-serum of a dog which was being immunized with B. icteroides would in dilu- tions of 1 to 5000 promptly arrest motility and ag- glutinate the hog-cholera bacillus. After testing various dilutions of this serum from 1 to 100 to 1 to 5000 we could observe no difference in its agglutina- tive reaction upon B. icteroides and B. cholera suis. We have recently obtained, through the kindness of Surgeon General Sternberg, a specimen of San- arelli’s icteroides serum from Rio Janeiro, which, in dilutions of 1 to 120,000, promptly arrests the motility and agglutinates bacillus icte- roides. In the same dilution this serum immediately arrests the motility of the hog-cholera bacillus, but does not bring about agglutination of the bacilli un- til at the end of about three hours. In a dilution of 1 to 30,000 agglutination commences within ten minutes and is complete at the end of one hour. The groups of bacilli are smaller than occurs with B. icteroides. In rejecting B. icteroides as the specific cause of yellow fever Novy emphasizes the extreme resistance of this bacillus to low temperatures1. We have ll‘The Etiology of Yellow Fever,” Medical News, p. 368, Sep- tember 17, 1898. 6 found Sanarelli’s bacillus to preserve its vitality and virulency after twenty days continuous freezing at — io° C. (140 F.). That the hog-cholera bacillus is also quite resistant to low temperatures has been proven by the observations of Smith, and by the fact of its survival, notwithstanding the extreme severity of winter in our Northwestern States. Putting together, therefore, the remarkable cul- tural resemblances of these two bacilli, and the similarity of their pathogenic action as shown in guinea-pigs, rabbits, pigeons, dogs, and hogs, we venture to express the opinion that ttir bacillus icteroides (Sanarelli) is a variety ot the hog-cholera bacillus, and that it should be considered only as a secondary invader in yellow fever. We find that bacillus x (Sternberg) presents marked differ- ences from the foregoing micro-organisms, both as regards its biologic characters as well as its patho- genic action toward animals. Reserving for future publication a more detailed description of our ob- servations, it will suffice to here state our opinion that bacillus x should be placed with the colon group. The Medical News ESTABLISHED IN 1843. A WEEKLY MEDICAL NEWSPAPER. Subscription, $4.00 per Annum. The American Journal OF THE Medical Sciences ESTABLISHED IN 1820. A MONTHLY MEDICAL MAGAZINE. Subscription, $4.00 per Annum. Progressive Medicine QUARTERLY, 400-500 PAGES, ILLUSTRATED. Subscription, $10.00 per Annum. COMBINATION RATES American Journal Medical News Progressive Medicine Medical News Visiting List.. Medical News Formulary ... ALONE .$ 4-oo . 4.00 / . IO.CO . 1.25 IN COMBINATION $7.50 315.00 $15-75 • $i6 I 50, net . In all 320.75 for $16 ‘‘Progressive Medicine,” and “Journal” or “News,” $13. “Journal,” “News,” “Visiting List” and “Formulary,” 38-50. LEA BROTHERS & CO., PUBLISHERS, 706-8-10 Sansom St., Philadelphia. in Fifth Ave , New York,