The estimated daily supply of milk in Norwalk was 3,500 quarts. Dealer H. furnished 450 quarts, or about one-eighth of the whole, whereas he had twenty-seven twenty-ninths of the scarlet fever cases on his route.

H. bought his milk from three producers. There were no cases of disease in the family of the milk dealer nor in those of two of the producers, A. and B. but on the third producing farm, K., a case of scarlet fever was found. This farm was in the Bald Hill district. The district school had opened September 7 with a registration of 23 pupils. On September 20 ore of the pupils fell ill with scarlet fever; other cases followed, and the school was closed October 19. In all there were 20 cases, all in school children or in those coming in contact with them. Two of the above cases, living near farm K., were exceedingly mild and frequently visited and played at this farm with K.'s son, a lad of 4 years. This son broke out with a scarlatinous rash October 24.

Milk from this farm was carted to Norwalk and all of it sold to, and delivered by, dealer H., who placed the cans of milk from K. in his wagons with that from the other two producers, A. and B. No attempt was made to keep the cans separate, and, therefore, one day part of his customers might receive K.'s milk and the next day it would be delivered to others. H. supplied about 300 families, of which 24 were invaded. The sale of this milk was stopped November 7. The number of cases and the dates on which they occurred would indicate that the milk was not continuously infected. During the outbreak several cases of sore throat occurred among users of H.'s milk, which may possibly have had some casual relation to the infectious milk.

It would seem that cases of scarlet fever belonging to a school outbreak and visiting a dairy farm, and possibly also the boy on the farm, infected from his playmates, were the source or sources rendering the milk infective. The relation here of the two outbreaks is of interest, the one spread by school contact being the original source of the milk epidemic.

DIPHTHERIA.

Diphtheria epidemics apparently due to milk began to be reported in 1877 and 1878 in England. In certain cases the suspected milk came from herds where cows were found suffering from an eruptive disease of the udder, and this was thought to be the source of the infection. In this connection Klein conducted some experiments on cows with the Klebs-Löffler bacillus. He took healthy milch cows and inoculated them subcutaneously in the shoulder with 1 cubic centimeter of a broth culture of the Klebs-Löffler bacillus taken from a

a Klein, Report Med. Officer, Loc. Govt. Board, London, 1889, p. 167,

human case. These cows became ill, had a rise in temperature, and on the fifth day there appeared upon the udder an eruption characterized by papules, vesicles, and crusts. He states that he isolated the B. diphtheriae from the vesicles, pustules, and milk. Other experimenters have however failed to get similar results. The Klebs-Löffler bacillus has been isolated from market milk by Bowhill, Eyre," Klein, and Dean and Todd.'

KLEBS-LÖFFLER BACILLI IN MILK.

Dean and Todd reported that in certain families supplied with milk from two cows there occurred 2 cases of clinically typical diphtheria and 3 of sore throat, that in one family using the milk only after sterilization no case occurred. Inspection of the cows showed papules, crusts, and ulcers on the teats and udders. One of the cows seemed well and gave apparently normal milk; the other had a mammitis and gave a scanty, ropy, semipurulent and slightly bloodtinged milk. Cultures were made from the throat of one of the diphtheria patients and also from the ulcers and milk of each cow, and typical Klebs-Löffler bacilli were isolated in all cases. The milk of the cow with mammitis also contained streptococci. The bacillus isolated was virulent and markedly pathogenic to guinea pigs, but diphtheria antitoxin protected guinea pigs against large doses. The udder eruption was shown to be contagious to cows and capable of spread by the hands of the milker, but no B. diphtheria were found in vesicles and ulcers of the secondary bovine cases. Calves were not protected from this disease by diphtheria antitoxin, nor by this disease from cowpox. The conclusions drawn were that the ulcers on the udders had become secondarily infected with B. diphtheria, probably accidentally from some apparently healthy throat, and that the udder affection was a separate disease.

Eyre has shown the ability of the B. diphtheria to proliferate in raw milk drawn from the cow under aseptic conditions as follows:

" Abbott (A. C.), Jour. Path. & Bact., 1894, II, p. 35. Ritter, Centralblatt f. Bakt., Referat, 1896, XIX, p. 662. Bowhill, Veterinary Record, 1899, April 8th.

Eyre, Brit., Med., Jour., 1899., II, p. 586.

Klein, Journal Hygiene, Camb., 1901, I, p. 85.

1 Dean & Todd, Jour. Hygiene, Camb., 1902, II, p. 194. Eyre, loco citato.

24907-Bull. 41-08- -3

EXPLANATION OF DIAGRAM III.

JH, RBN, ETT, OH, JM B, and C FJ are the farmers producing milk.

A is the milk dealer delivering milk in both Milton and Dorchester. B is the milk dealer delivering milk in Hyde Park.

The lines connecting the producing farms and the milk dealers show to which dairy the farmer sold his milk.

The large squares represent Milton, Dorchester, and Hyde Park. The dash-lines extending from A to B into the towns represent the milk routes carrying the supposedly infectious milk.

Each dot represents a case of diphtheria and is placed on the milk route from which it was supplied.

C, D, E, F, G, and H represent the other dairies selling milk. The lines extending from them into the towns represent their routes and are inserted to show their freedom from diphtheria cases.

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SUMMARY OF EPIDEMICS.

Of the 23 diphtheria epidemics reported as spread by milk and compiled since 1895, 15 occurred in the United States and 8 in Great Britain; cases of the diseases occurred at the producing farm, distributing dairy or milk shop at such a time as to have been the possible cause of the outbreak in 18 cases; the diseased person milked the cows in 4; the same person nursed the sick and handled the milk in 1; the outbreak was supposed to be due to disease of the cows in 2; all cases of the disease were reported as living in households supplied with the suspected milk in 15 instances; measures taken upon the presumption that milk was the carrier of infection were reported as followed by subsidence of the outbreak in 5 cases; the Klebs-Löffler bacillus was isolated from the suspected milk in 2 of the epidemics. The following outbreak is one of many interesting examples:

OUTBREAK OF DIPHTHERIA IN DORCHESTER, MILTON, AND HYDE PARK.

On April 13, 1907, after a period of comparative freedom from diphtheria, there were reported to the board of health of the town of Milton 11 cases of that disease. This sudden explosion caused very naturally a feeling of grave apprehension on the part of the local health authorities. The following is an account of the epidemic: Cases of diphtheria were reported in Milton as follows: April 12, 1 case; 13, 11 cases; 14, 1 case; 15, 4 cases (of these 4 cases, 3 were in the same house and secondary to a case which had developed before the 12th and can therefore be considered as not belonging to this explosive outbreak); 16, 1 case. In Dorchester cases were reported as follows: April 12, 6 cases; 13, 19 cases; 14, 11 cases. In Hyde Park the number and dates were: April 13, 2 cases; 14, 5 cases; 15, 6 cases; 16, 1 case; 17, 3 cases, and 19, 1 case.

The following table shows the relationship of the cases in the different places:

Monthly Bulletin, State board of health, Mass., May, 1907, vol. 2, No. 5,

p. 117.