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SERUM REACTION OF GOATS AFTER TREATMENT WITH DRUGS.

On March 29, 1906, blood was drawn from 12 of the goats at the station which had been under the medicinal treatment for two months. Of this number 7 gave a good, 3 an imperfect, and 2 no reaction, thus showing little hope of eradicating the infection by internal drug administration. While the serum might probably have reacted as a result of the presence of agglutinins formed before the treatment became effective, even though no living Micrococcus melitensis existed in the blood or tissues, it was not thought advisable to assume any risk with a disease of this character, and therefore no further lines of treatment were attempted.

It should be stated in connection with the medicinal treatment of these goats that at all times attempts were made to segregate the infected and suspicious from the noninfected animals. The continued spread of the disease at Athenia is apparently explained by the fact that the blood of the goatherd, a native of Malta and apparently in robust health, was subsequently found to react to the agglutination test, and it is not at all unlikely that he was either an ambulatory case or a "bacillus carrier," and that he was the cause of the infection in at least some of the reacting goats, inasmuch as his quarters were in the one-story building with them. After the animals arrived at Bethesda a large number of isolated pens, separated by at least 25 feet of ground, were used for stabling them, and not more than two goats were placed in each pen. If one of the two reacted or gave a suspicious reaction, the nonreacting animal was immediately removed to another previously unoccupied pen, and the original pen and feeding troughs were then thoroughly disinfected and the bedding, litter, etc., burned.

HEALTH OF GOATS AT BUREAU EXPERIMENT STATION.

The general condition of the goats after their arrival at the Bureau Experiment Station grew from bad to worse. They were multiplying rapidly, however, some of the nannies having twins and several having triplets. It seemed that they were unable to stand the climatic conditions, and adults and kids died in considerable numbers. The adults on post-mortem showed the cause of death to be due to various conditions, by far the most prevalent being pneumonia and pleurisy. Septic metritis following difficult parturition caused some deaths, gastro-enteritis was responsible for other fatalities, and in one case acute pancreatitis with fat necrosis was the cause.

The kids were practically all affected with articular rheumatism and their joints became swollen and in many cases permanent deformities resulted. All the kids which came to post-mortem from

Bethesda showed severe infestation with intestinal coccidiosis. Pneumonia, goiter, and enteritis also caused fatalities.

Cultures were made from the viscera of many of the dead animals. In three adult cases the Micrococcus melitensis was recovered, cultures being obtained from the spleens of these animals in each instance.

Although the lymphatic glands, especially the mesenterics, were markedly enlarged and edematous in a number of the kids, which is one of the main anatomical points of evidence of infection in goats, the Micrococcus melitensis was recovered from only one of these animals.

FINAL AGGLUTINATION TESTS.

On June 1, 1906, the blood of each of the remaining adults, 25 in number, was again tested, and 8 good, 8 imperfect, and 9 negative reactions were obtained.

From July 2 to July 18, 1906, all the remaining kids, totaling 57, were tested, the results showing 21 reactions and 36 which did not respond. As it was the intention to kill off all the kids whose blood showed any evidence of agglutination, imperfect reactions were all classed as reactions. The 21 reacting kids, together with the 8 adults which gave a good reaction, were killed after this test.

On October 17, 1906, the 17 remaining adults were again tested, and 2 of the 8 which on June 1 had given an imperfect reaction now gave a good reaction.

By this time it had become thoroughly recognized by all parties concerned that the use of the goats for the purposes for which they had been imported would be accompanied with considerable danger of serious results. It was therefore decided to dispose of the herd, and in November, over a year after their arrival, all the remaining goats, including the kids, were destroyed.

CONCLUSIONS.

1. It has been definitely demonstrated that the Micrococcus melitensis, the organism of Malta fever, has a more or less passive existence in the body of Maltese goats, exercising its pathogenic effect when it gains entrance to the human body.

2. These goats, when carriers of the virus of Malta fever, are one of the important factors, if not the principal factor, in the dissemination of this disease, through the ingestion of their milk by human beings.

3. Goats infected with Malta fever eliminate the causative agent of the disease in both the milk and the urine.

4. All the available evidence points to contaminated food as the vehicle by which the goats become infected with the organism of Malta fever. The urine of infected goats and of ambulatory cases

in man at times contains the Micrococcus melitensis, so that normal goats feeding on material which had come in contact with such urine are readily infected. Thus the frequency and the method of infection in goats are quite easily explained.

5. An elderly woman who had consumed a considerable quantity of the Maltese goats' milk at the Athenia quarantine station had a typical attack of Malta fever, diagnosed by the symptoms and the reaction of her blood serum to the agglutination test. This case is the first one recorded in which infection by goats' milk is directly demonstrated when contact infection and other modes of exposure were entirely eliminated.

6. So long as Malta fever remains so prevalent in the Island of Malta, and such a large percentage of the native goats are passive carriers of the Micrococcus melitensis, it will be impracticable to attempt to introduce these animals into the United States. Even if they were assuredly free from Micrococcus melitensis, it is doubtful, on account of climatic conditions, whether they could be profitably bred in this country, except in the extreme Southern States.

THE VITALITY OF TYPHOID BACILLI IN MILK AND BUTTER.

By HENRY J. WASHBURN,

Senior Pathologist, Pathological Division.

TYPHOID CASES TRACEABLE TO MILK.

The investigation of the cases of typhoid fever which have occurred in the District of Columbia during the past three years shows that one of the important factors in the spread of this disease is to be found in the market milk which is supplied to District inhabitants. The Hygienic Laboratory of the United States Public Health and Marine-Hospital Service found that 11 per cent of the cases in the year 1906 owed their origin to infected milk, in 1907 about 9 per cent of the cases were similarly caused, and in 1908 the percentage reached about 10 per cent, which is the average percentage shown by their records for the three years above mentioned. These percentages were based upon the number of cases actually traced to infected milk." Other investigators have claimed that dairy products were the conveyers of this disease in as high as 15 per cent of cases, which only tends to emphasize the difficulties that investigators always encounter when they attempt to trace the cases of typhoid fever in any outbreak to an incontestable origin.

Taking into consideration the fact that typhoid fever is a disease that is present in all countries, at all seasons of the year, and among all classes and conditions of people, it at once becomes evident that 10 per cent of the annual aggregate number of attacks represents a large amount of preventable sickness and suffering.

SOURCES OF TYPHOID CONTAMINATION IN MILK AND ITS

PRODUCTS.

The typhoid-fever organism thrives admirably in milk at suitable temperatures and reproduces with great rapidity when in this medium under favorable conditions. Milk as it is drawn from the cow does not contain typhoid bacilli, but it may quickly become contaminated from extraneous sources and is then ready to convey the infection to the person using it, either as a beverage or in the form of butter or cheese manufactured from it. Numerous tests have shown that even though typhoid bacilli are administered to a dairy cow in great numbers by drenching they will be so disposed of during the

"Hygienic Laboratory Bulletin 35.

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