George Soper on Mary Mallon



The appearance of the following article in The Military Surgeon has a particular appropriateness in spite of the fact that the history of this remarkable woman has been confined, so far as known, to persons in civil life.  It is appropriate for a number of reasons.

First, the story, substantially as it appears on these pages, formed an address, which Major Soper delivered before the Surgeons of the Sixth Division to which he was attached as epidemiologist in the Army in 1913.

Second, typhoid has been brought under control largely by reason of work done to prevent the very kind of infection, which “Typhoid Mary” produced.  Investigation showed that a large part of the typhoid in the Spanish American War was due to contact, and the preventive treatment by inoculation which has been compulsory among United States troops since 1911 has been particularly directed against this method of transmission.  And in the present war the disease has been combated not only by attention to sanitation and inoculation, but by examining cooks and other food handlers for the carrier state in order that no person such as “Typhoid Mary” might be allowed to spread infectious material even among those who were immunized against it.

Since “Typhoid Mary” was discovered, the whole problem of carriers in relation to infectious diseases has assumed an immense importance, an importance which is recognized in every country where effective public health work is done and in every army where communicable disease has been brought under control.

The literature of typhoid now contains many examples of the carrier state such as “Typhoid Mary” exhibited; there have been some carriers who have produced more cases, but it is safe to say that it has fallen to the lot of no person to give by example a more striking lesson of the need of personal precautions in the control of disease than has been afforded by this remarkable woman.  Her interesting history contains lessons which should be carefully heeded by everybody, whether in the Army or out of it.

Surgeon General, U. S. Army.

THIS is the story of the cook who produced a series of epidemics of typhoid fever and was finally discovered and locked up by the New York City Department of Health. Her general history up to that point is widely known, although few details of it can be given by most persons.  Her history after her arrest forms a fitting climax to her career. How she disappeared, produced more typhoid and was caught again, is now set down for the first time.

The great amount of attention which the case has received is due entirely to the natural interest which it possesses. The ease has never been exploited for the dramatic elements which it contains, although these fairly crowd one another throughout the narrative. The circumstances of Typhoid Mary’s discovery were simply announced be-fore the Biological Society of Washington, D. C., April 6, 1907, in a brief paper. This paper subsequently appeared in a medical journal.1 Since then no authoritative account of the ease has been written. Most of the knowledge which the. world possesses of it has been obtained from newspaper accounts of some of Mary’s interesting movements since her original arrest.

Many inquiries have been received by me as to the history of Typhoid Mary since her first arrest, and ~though I have had no official connection with the matter since I brought the details to the attention of the New York City Department of Health on March 11, 1907, I seem to be regarded as the person to whom all such inquiries showed be addressed.

It is in view of the scientific and popular interest in the subject which has continued now for more than a dozen years, that the following notes are made, the intention being to review the essential facts and to give notice to Typhoid Mary’s movements since she was first taken into custody by the New York City Department of Health.


In the winter of 1906 I was called upon by Mr. George Thompson, of New York City, to investigate a household epidemic which had broken out in the latter part of the preceding August at the Thompson country place at Oyster Bay.  The epidemic had been studied by experts immediately after it took place, and there were a number of typewritten reports upon it, but its cause had not positively been ascertained. It was thought by the owner that, unless the mystery surrounding the outbreak could be satisfactorily cleared up, it would be impossible to find desirable tenants for the property during the coming season. The essential facts concerning the investigation follow: Six persons in a household of eleven were attacked with typhoid fever. The house was large, surrounded with ample grounds, in a desirable part of the village, among other handsome places, and had been rented for the summer by a New York banker, Charles Henry Warren.

The first person to be taken sick fell ill on August 27, and the last on September 3. The diagnosis was positive. Two of the patients were sent to the Nassau Hospital at Mineola, and the others were attended by capable physicians at Oyster Bay. None of the subsequent cases apparently resulted from the first. They seemed all to have been original infections.  But, whether the disease was transmitted locally or not, the point of interest lay in the origin of the first case.

Typhoid was an unusual disease in Oyster Bay. At the time of the outbreak, 10 other cases were known. None followed. The milk supply, cream, water and other articles of food which might have been implicated were one by one carefully eliminated as _ possible causes. The drainage was examined and found satisfactory. Extreme care was used in this part of the investigation in view of the fact that there was a firmly settled belief on the part of many persons that the water had become contaminated from cesspools, a privy vault or stable manure pit. Analyses of the water were made independently by two competent chemists and flourescein was used to study the possibilities of underground percolation. As a result of this particular study it did not seem to me that the water theory was tenable. I was led from the proper track for a time by being informed that the family was extremely fond of soft clams and that supplies of these shell fish had frequently been obtained from an Indian woman who lived in a tent on the beach, not far from the house, and whose supplies of clams were sometimes taken from places that were not improbably polluted with sewage.

But if clams had been responsible for the outbreak, it did not seem clear why the fever should have been confined to this house, because soft clams formed a common article of diet among the native inhabitants of Oyster Bay.  On inquiring closely, it was found that no clams had been eaten for six weeks before the outbreak of typhoid, and six weeks was too long a period for an epidemic of this character to remain undeveloped. In my opinion the infectious matter which produced the epidemic had been taken with food or drink on, or before, August 20.

The history of the house with regard to typhoid showed that no case had occurred on the premises or been nursed there, nor was it believed that a convalescent had visited it in thirteen years, and the house had been occupied every summer since then Attention was then concentrated on the first case of typhoid to determine whether the infection could have occurred during a temporary absence from Oyster Bay, and it was discovered that no person who was taken sick had been on a visit away from Oyster Bay for several weeks prior to the onset of the disease.

The social positions of the persons attacked differed decidedly. The first was a daughter of the family; the next two were maid-servants. Following this, in quick succession, were the wife, and then another daughter of the tenant, and finally a gardener who resided permanently at Oyster Bay and who had lived on the place for years. Believing that some event had occurred in the family or in Oyster Bay, which, properly studied, might give the clue to the cause of the epidemic, the immediate history of the household at this time was carefully inquired into. This gave the key to the situation.

It was found that the family had changed cooks on August 4, about three weeks before the epidemic broke out.  Little was known about the new cook’s history. She had been engaged at an employment bureau which gave her a good recommendation.  She remained in the family only a short time, leaving about three weeks after the outbreak of typhoid occurred.  Her present whereabouts were unknown.

The cook was described as an Irish woman about forty years of age, intelligent, tall, heavy, single and non-communicative. She seemed to be in perfect health. She was not known ever to have had an attack of typhoid.

Here was by all means the most important clue which had come to my notice. II this woman could be found and questioned, it seemed likely that she could give facts from which the cause of the epidemic could be ascertained. I had seen typhoid spread in large epidemics under circumstances which led me to believe that it should be regarded as a contagious disease, and I had so dealt with it when acting as expert for the State of New York in handling the epidemic of 1,300 cases at Ithaca in 1903,2 and later as expert of the city of Watertown, N.Y., in fighting an epidemic of 600 cases in 1904.

When, after much difficulty, the cook was found, no information of value was obtainable from her. She refused to speak to me or to anyone about herself or her history, except on matters which she found were already known. Her former employers gave freely what information they could. but their minds were not wholly free from bias. Nearly all the epidemics which I was inquiring into had been investigated soon after they occurred and had been explained in a different way.  The answers to my questions were therefore unconsciously framed so as to convince me that the original explanations were correct.
Curiously enough the greatest help came from a quarter which was least expected. The office through which Mary had secured some of her situations gave me all the assistance which it possessed. This office, conducted in the name of a woman, was really run by a man. For some good reason he did not allow his own name to be known. Whether by aptitude, training, or both, this person possessed many of the attributes of a good investigator.  Without his help Typhoid Mary could not have been found.

In passing, it is interesting to observe that nobody who hired Mary seems to have inquired personally into her references. It seems that the names of some of her former employers were available, but it appears not to be the custom of the patrons of fashionable employment bureaus to inquire deeply into the personal history of the servants. Mary always was accepted on the recommendation of the proprietor. He was trusted to run a genuine intelligence bureau and it is but right to say that, on the whole, he discharged his obligations admirably.

The effort to work out Typhoid Mary’s history was only partly successful. There were many false dews and puzzling circumstances. The mystery which had at first surrounded her continued and was often completely baffling. Sometimes it was somebody’s memory which was at fault–few housekeepers seem to know anything about their cooks, much less recall the food which they have eaten weeks and months ago. Yet this information, in some instances, was indispensable.

Sometimes it appears that persons were deliberately refusing to tell what they knew. Twice, I think, I talked with members of Mary’s family, but I could never be sure of it.  Servants who had been associated with her never gave any help. Try as I would, Typhoid Mary’s whereabouts for only part of the ten years before the Oyster Bay outbreak could be determined with unmistakable certainty. About two years of the preceding five remained unaccounted for. In ten years she is known to have worked for eight families and in seven of these typhoid had occurred. She had always escaped in the epidemics with which she had been connected.

A summary of the principal epidemics follows

In 1904 there was an outbreak at the summer residence of Henry Gilsey, Esq., at Sands Point, N.Y. The household consisted of eleven persons, seven of whom were servants.  The house was rented on June 1. On June 8 typhoid began to appear  The first case was that of a laundress. Following this three other persons were taken sick in succession. None of the family was attacked. The Sands Point epidemic was confined to the house where the servants lived. There were no other cases before or after, either in the household or in the village. The cause of the outbreak was believed to be connected in some way with the servants’ quarters.

In 1902 a severe outbreak occurred in the family of a New York lawyer at Dark Harbor, Maine. Mr. Coleman Drayton had rented a cottage for the summer and just before leaving New York to occupy it with his family had engaged Mary Mallon to act as cook. Seven members of this household of nine were presently attacked.  In addition, a trained nurse who came in by the day took sick.  The first case occurred two weeks after the arrival) on June 17.  One week later another case occurred; two days later there was a third; the remainder followed rapidly. The only persons who escaped were the cook and . Drayton himself, and he had had an attack some years before. These two faced together the burden and anxiety as, one by one, every other occupant of the house fell ill.  Drayton felt so grateful to the cook for the help which she gave him during the epidemic that at the end of the epidemic he made her a handsome present of money in addition to her wages, little thinking that the cause of the whole trouble lay at her door.

The Dark Harbor epidemic was investigated at the time and a written report was made upon it. The infection was thought to have been brought to the house by the maid-servant who was the first to be taken ill. It seems that the servants had access to a water tank in the top of  the house and it was supposed that this tank became polluted by the first person who was attacked, thus infecting the entire household. How the original case was produced was not explained, but it was assumed with the easy logic which is familiar in many such investigations that it was contracted elsewhere.

Mary Mallon’s history before she went to Dark Harbor is not clear. In 1901-02 she lived about eleven months with one family. Here a laundress was taken ill and removed to the Roosevelt Hospital, December 9, 1901. This attack occurred one month after the cook’s arrival. Un-like the other outbreaks, the  cause of the attack was not investigated at the time, and full information concerning it has not been available.

The earliest record of Mary Mallon’s employment is in a New York family which had a summer residence at Mamaroneck, New York. In this instance a young man who made a visit to the family was attacked, his illness dating from September 4, 1904. The cook left a few days after the onset of this illness. It is interesting to observe that she had been in the family for three years without apparently being connected in any way with ty’phoid before this. It was believed at the time that the young man had contracted his typhoid before he came to visit the family.

Subsequent to her employment at Oyster Bay, Mary Mallon went to live with a family at Tuxedo, New York.  She remained about one month -to be exact, from September 21 to October 27, 1906.  On October 5, fourteen days after her arrival, a laundress was taken sick with typhoid fever and removed to St. Joseph’s Hospital, Patterson. No other case had been known in Tuxedo for several years.


When at last the cook’s final whereabouts were ascertained, it was discovered that two cases of typhoid had recently broken out in the household where she was employed.  These occurred a few weeks after her arrival. One patient, a chambermaid, was taken sick January 23, -1907, and removed to the Presbyterian Hospital. The doctor was first called to see the other patient, a daughter of the owner of the house, on February 8. This second case resulted fatally on February 23, 1907, the only fatal case in the record up to this time. A period of two months elapsed between the beginning of the employment of the cook and the first case. There was some doubt about the diagnosis of these cases at the time of my investigation and no opinion had been formed as to their origin. The cook was about to leave the New York house.

It was at this house that I had my first interview with Mary. I expected to find a person who would be as desirous as I was for an explanation of the way in which the typhoid had followed her. Certainly she could not have failed to be impressed by the strange fatality with which the disease had broken out wherever she went. It must have looked as though it was pursuing her.  Could she be connected with it in any way? Possibly she had even thought that she had produced the epidemics.

If  she were implicated in the outbreaks it was, of course, innocently. I supposed that she would be glad to know the truth and to be shown how to take such precautions as would protect those about her against Infection. I thought I could count upon her corporation in clearing up some of the mystery which surrounded her past. I hoped that we I might work out together the complete history of the case and make suitable plans for the protection of her associates in the future. Science and humanitarian considerations made it necessary to clear up the whole matter.

My interview was short.  It started in the kitchen and ended almost immediately at the basement door. Reason, at least in the forms in which I was acquainted with it, proved unavailing. My point of view was not acceptable and the claims of science and humanity were unavailing. I never felt more helpless.

The next interview was staged more deliberately. Mary had a friend whom she often visited at night in the top of a Third Avenue tenement. He kindly offered to manage for the meeting and one night, after her work was done, I awaited her with a physician, Dr. Bert Hoobler, one of my former assistants, whom I had called to help. We waited at the head of the stairs in the Third Avenue house.

At length Mary Mallon came. Dr. Hoobler and I described the situation with as much tact and judgment as we possessed. We explained our suspicions. We pointed out the need of examinations which might reveal the source of the infectious matter which Mary was, to a practical certainty, producing.  We wanted a small sample of urine, one of feces and one of blood.  The urine and feces were to be tested for typhoid bacilli and the blood for the Widal reaction. We hoped we could get some information from Mary at the same time.

Indignant and peremptory denials met our appeals. We were unable to make any headway.  Mary’s position was like that of the lawyer who, on being told by the judge that the facts were all against his client, said that he proposed to deny the facts.  Mary denied that she was a carrier.  She referred to the Dark Harbor outbreak for proof of her helpfulness and to the gift from her employer there as testimony of the same. Far from causing typhoid, she had helped to cure it. Nothing could alter her position.  As Mary’s attitude toward us at this point could in no sense be interpreted as cordial, we were glad to close the interview and get down to the street.  We concluded that it would be hopeless to try again.

Here my investigation came to an end.  It was evident that, although I had succeeded in collecting only fragments of her history, there was a remarkable resemblance between these parts.  In each instance one or more cases of typhoid had occurred in households after the cook had arrived, or among people who had come to live near her and eaten of the food which she prepared.  In every instance the families had ample means and lived well, as the saying is.

The bearing which wealth may have on the chance of infection may not at once be apparent, but it was taken carefully into account in this investigation. People who live as did the family concerned in these epidemics are almost isolated from infection by their cooks by reason of the fact that nearly everything they eat is subjected to the heat of cooking after it leaves the cook’s hands. The heat kills the germs The cook does not cut the bread or arrange the salad or fruit, for ex-ample. All such work is done by a butler, footman or waitress, d~ pending upon the manner in which the housework is organized. The cook comes in much more direct contact with the cooked food of the servants; a fact which probably accounts for the relatively larger number of servants attacked in the several epidemics. Each household had consisted of four or five in the family and from five to seven servants.  Four of those attacked had been laundresses, and two gardeners permanently attached to the country places where the epidemics had broken out.  All but two of the outbreaks had occurred in the country. The cook had escaped sickness in every instance. In  only one case could I find that she had worked in a family where no typhoid occurred, and as this family consisted only of three people of advanced age it is not improbable that they were immune. In all, there were twenty-six cases and one death; twenty-four of these cases had occurred in the preceding five years.

Believing that enough had been learned to show that the cook was a competent cause of typhoid, I laid the facts concerning the four principal epidemics before Dr. Herman M. Briggs, Medical Officer of Health of the New York City Department of Health, with the suggestion that the woman be taken into custody by the department and her excretions made the subject of careful bacteriological examination. I had been unable to obtain her consent to any examination whatever.

The department acted favorably on this suggestion and, after considerable difficulty, during which a number of officers had to be called upon to help, the cook was removed to the Detention Hospital of the Health Department. She reached there on March 19, 1907. She was placed in charge of Dr. Robert J. Wilson, Superintendent of the Department of Hospitals, and Dr. William H. Park, Chief of the Research Laboratories of the Department of Health. Dr. M. Goodwin did the bacteriological work under Dr. Park’s direction.

My third and last attempt at an interview was after her arrest. Mary was in a separate room at the Detention Hospital. I explained that I had come to get some information from her. It was desirable to know whether she had ever had an attack of typhoid and, if so, where and when. Would she consent to give a complete history of her experience with typhoid? The information might help many. It could not possibly hurt her. It might prove very helpful in explaining her case. As matters stood, nobody accused her of deliberately intending any harm. If possible, she was to be freed from her disease-producing capacity.

This interview was shorter than the other two. Without uttering a word Mary retreated with dignity to the toilet, leaving me standing alone in the room.

It was expected by me that the germs might be found in the urine, but more probably in the stools. None was found in the urine. The stools contained the germs in great numbers. Daily examinations made for over two weeks failed only twice to reveal the presence of the Bacillus typhoid and on these occasions the sample taken was perhaps too small to reveal them. The blood gave a positive Widal reaction. The cook appeared to be in perfect health.

The feces were examined on an average of three times a week from March 20 to November 16, 1907, and in only a comparatively few instances did the investigators fail to find the bacilli. During the summer months the culture plates contained only a few typhoid-like colonies. In July there were five consecutive negative tests followed by a positive one.

During August the stool showed no typhoid; in September they began to appear again; from September 11 to October 14, 1907, the feces failed to yield typhoid bacilli. During this time the patient’s diet was carefully regulated and she was receiving mild laxatives.  On October 16, 1907, a very thorough test showed that the germs were again present. From October 16, 1907, to February 5, 1908, weekly examinations of the stools gave, with only two exceptions, from 25 to 50 per cent typhoid- like colonies on the culture plates. These exceptions were on November 13 and December 4, when no typhoid was found. The implication was plain. The cook was virtually a living culture tube in which the germs of typhoid multiplied and from which they escaped in the movements from her bowels. When at toilet her hands became soiled, perhaps unconsciously and invisibly so. When she pre-pared a meal, the germs were washed and rubbed from her fingers into the food. No housekeeper ever gave me to understand that Mary was a particularly clean cook. In the Oyster Bay outbreak, which was studied with more particularity than the others, the infectious matter is believed to have been carried from the cook’s hands to the people who were later taken sick by means of ice cream containing cut -up peaches.  Mary prepared this herself. In this instance no heat sterilized the washings from her hands. Mary Mallon was kept virtually a prisoner by the Department of Health for three years. At first she was held at the hospital for contagious diseases at the foot of East 16th Street, Manhattan; later she was removed to Riverside Hospital on North Brother’s Island in the East River, between Hell Gate and Long Island Sound.

She was employed in various ways, sometimes as laundress. She was allowed to receive friends and enjoyed such privileges as were possible, but she never became reconciled to her detention.

Two legal actions were brought to secure her release. The claims made on her behalf were that she was being deprived of her liberty without ever having committed a crime or knowingly having done injury to any persons or property; she was held without being given a hearing; she was apparently under life sentence; it was contrary to the Constitution of the United States to hold her under the circumstances; such action on the part of the authorities was without precedent. These legal actions were argued with much ability. It was expected that, if she won, she would recover heavy damages.

The case attracted a great deal of public notice, some of the news-papers going to the extent of printing the arguments with illustrations of the unfortunate woman. The courts held that the Department of Health acted within its rights in keeping Mary Mallon in custody and that they were well serving the public interests in refusing to release her. Public sentiment, to judge by the illustrations, was a trifle mixed. On the one hand Mary was pictured as frying deadly typhoid bacilli the size of sausages ill preparation for the family meal, and on the other she was shown sitting lone and dejected on her island with a mongrel dog as her solitary companion. Punch, the famous English funny paper, devoted a column of poetry to the case.


Although the courts refused to order her release, there was a good deal of sympathy for Typhoid Mary. Whatever could be said of the consequences 0f her cooking, she had been an innocent offender. She was careless in her personal habits, but so are most cooks. If she was a deadly germ producer, so were thousands of others who were enjoying their liberty. To many persons who did not know Mary it seemed that she ought to be given her liberty.

In the year 1910, soon after a change was made in the administrative head of the Department of Health, Mary Mallon was voluntarily released on her promise not to take employment as a cook nor engage in an occupation which would bring her in contact with food. It was thought that she had learned in three years how dangerous she was and how to avoid infecting people. She was forbidden to cook or otherwise handle the food of others and was required to report periodically to the Department of Health. For awhile she kept her promise. Then she broke her parole and disappeared. She was lost sight of for nearly five years. I have been unable to learn her complete history during this period, but from the fragments which have been collected, it is apparent that she continued to enact her hateful r6le of typhoid producer. Due to the fact that the woman assumed various names and left little trace behind to indicate her whereabouts, it was not possible to learn all that was desired.

She seems to have produced two cases of typhoid in a sanatorium at New Foundland, N.J., where she was employed in 1914, and another case in New York City in the same year in a small family where she was living under an assumed name with a friend. This, however, is anticipating the end of the story.

Mary Mallon came  to light for the second time under circumstances which were the most dramatic of her entire career. In January and February, 1915, an outbreak of typhoid occurred in the Sloane Hospital for Women on West 59th Street, New York City.

In this epidemic there were twenty-five cases; they were mostly among the nurses and other attendants of the institution. The Sloane Hospital is one of the most capably managed institutions of its kind in America, and in its attention to every sanitary requirement is intended to be a model for the teaching of students in the College of Physicians and Surgeons of which it is practically a part.  In his conduct of the hospital and in his lectures to his students, it was the custom of Dr. Edwin B. Cragin, Attending Obstetrician and Gynecoloist, to lay his main emphasis upon scrupulous care of the hands. Yet, as Dr. Cragin freely acknowledged, this outbreak was produced by a woman whose hands became soiled with her excrement and who through careless and dirty habits infected the food of the inmates of the institution. ~ether she at first used sufficient care and later became indifferent is not known, but it is an interesting fact that Mary worked as cook in the hospital for about three months before the first case occurred. She knew, of course, the danger and how to avoid it. She knew that she was violating her agreement with the Department of Health in engaging in the occupation of cook.  That she took chances both with the lives of other people and with her own prospect for liberty and that she did this deliberately and in a hospital where the risk of detection and severe punishment were particularly great, argues a mental attitude which is difficult to explain. Aside from such behavior as this, Mary Mallon appears to be an unusually intelligent woman. She writes an excellent hand, and the composition of her letters leaves little room for criticism.

She possesses enough skill as a cook to command high wages and has been able to obtain work in the most desirable situations. Surely a mysterious, non-communicative, self-reliant, abundantly courageous person; a character apart, by nature and by circumstance, strangely chosen to bear the burden of a great lesson to the world. If she had learned and been willing to practice what she learned, she would not have had this costly lesson to teach.

Mary Mallon was officially known in the hospital by the name of ~s. Brown, but she was jokingly nicknamed “Typhoid Mary” by her fellow-servants when the epidemic occurred, for there were some who remembered the published accounts of Mary Mallon’s unfortunate experience of years ago. It was this nickname, implied in jest, that led the authorities to find her out.

When genuine suspicion began to focus upon her, Mary cleverly disappeared.  Before she could be apprehended, she moved to New Jersey and then to a home in Long Island.  She was finally traced to the Long Island house and was forcibly removed to the Riverside Hospital of the New York City Department of Health, refusing to go there without compulsion. She has been held by the Department of Health to June, 1919, without any prospect of again being released.


Mary status after her second arrest has been totally different from that which she possessed after her first. This is true both as to the legal aspects and public sympathy. whatever rights she once possessed as the innocent victim of an infected condition, precisely like that of hundreds of others who were free, were now lost. She was now a woman who could not claim innocence. She was known willfully and deliberately to have taken desperate  chances with human life, and this against the specific instructions of the Health Department.  She had been treated fairly; she had been given her liberty and was out on parole. She had abused her privilege; she had broken her parole.  She was a dangerous character and must be treated accordingly.

The total number or outbreaks of which Typhoid Mary is known to be the cause is ten; the total number of cases, fifty-one. Owing to the fact that only parts of her entire history are known, it is probable that the total number of outbreaks for which she is responsible is much larger than this record indicates. It would surprise nobody to learn that she had produced some extensive epidemics.

The case of Mary Mallon is of exceptional interest for a number of reasons. For one thing it illustrates one of the ways m which typhoid and other diseases may be spread without the real cause being suspected. It also shows that we should be slow in arriving at an opinion as to the origin of an outbreak.

It shows how carefully we showed select our cooks, and it calls attention in a startling manner to the fact that we ordinarily know very little about them. It confirms the truth of the adage that the more we pay the less we know about our servants.

The Mallon case affords a striking proof of the fact that our food is not infrequently contaminated by excrement. Here lies, perhaps, a common source of infection. Possibly many of the so-called diarrheas and food poisonings which occur may be ascribed to this cause. Some persons and some families seem to be especially prone to these upsets. Is it not possible that what appears to be special susceptibility is really infection from a nearby carrier in many of these instances?

The story of Typhoid Mary indicates how difficult it is to teach infected people to guard against infecting others. Mary had ample opportunity to know the danger which she constituted toward those whose food she prepared.  She knew from being told and she knew by experience.  She was aware of the penalty which she would suffer if she broke her parole and caused another outbreak. That she could have avoided spreading infection by obeying her instructions admits of no doubt. She knew that when she cooked she killed people, and yet she deliberately sought employment as a cook in a hospital.  why did she do this?

The case is least remarkable for the reason that it was the first of its kind to be worked out in America. It is surprising that nobody bad discovered a carrier before. They are now known to be rather common.

Somewhat similar investigations bad been made in Germany) and I make no claim of originality or for any other credit in her discovery. My interest and experience in the epidemiology of typhoid had been of long standing. I had read the address which Koch had delivered before the Kaiser Wilhelm’s Akademie, November 28, 1902, and his investigation into the prevalence of typhoid at Trier 3 and thought it was one of the most illuminating of documents. In fact it had been the basis of much of tile epidemic work with which I had been connected.

Koch’s address was not the only one printed about this time to show that healthy carriers might exist and give rise to typhoid.  Conradi and Drigalski4 had anticipated Koch and it was probably on the suggestion contained in their paper to the effect that with their new culture medium they had found typhoid bacilli in the stools of several well persons that Koch’s flying laboratory was sent to Trier and the ground prepared for his Kaiser Wilhelm’s Akademic address.

In the Festschrift Zum SeclizigstenGeburstag von Robert Koch, which appeared in 1903, there are several papers on the probable role of healthy carriers in producing typhoid. About this time Kayser, Klinger and others were publishing in Arbeiten aus dem Kaiserlichen Gesundheit-smate reports of cases which they found to be due to persons whose condition was much like Typhoid Mary’s.  Dr. Simon Flexner kindly called my attention to some of these references after I had concluded my work on the Mary Mallon case.

The literature of carriers has enormously increased in all countries since 1906. Instances of carriers causing large and small epidemics have multiplied by the score. The extent of the danger which is to be apprehended from this source and the steps to be taken to meet it have been discussed pro and con until it would seem that the grounds for a common agreement must long since have been reached.

There is agreement as to nearly everything except how to cure the carrier condition.  In some cases the germ focus can be reached and removed, in other cases this has so far proved impossible.  The trend of thought has entirely changed as to the cause of typhoid fever. Before the r6le of carriers was suspected, water supplies and milk were considered the principal means of transmission. The carrier idea led many to think that here was the principal explanation of the spread of typhoid.

The present thought is that carriers account for a varying proportion of the total typhoid in a region, the exact figure depending largely upon local circumstances.  Where water supplies, milk and other common vehicles of typhoid can be satisfactorily excluded from the reckoning carriers probably account for most of the cases.

As a result of research work done in Europe and America, it has been found the from 2 to 3 percent of all persons who have typhoid fever become chronic germ producers. Carriers have been divided into many classes groups some are intermittent, others continuous. A certain proportion permanently free themselves from infection and consequently their power to produce typhoid. Others never become free.

It has thus far been feasible to cure some of the carriers of their unfortunate condition, but there are others who cannot be cured. Experiments at disinfection and even the removal of the gall-bladder, which is generally the focus of the bacteria, have sometimes failed to produce the desired result.

What is to be done in order to protect ourselves from the danger of typhoid carriers?

  • First, it is desirable to discover the carriers. This is not easy. It is most readily done with the help of a good laboratory. The examination of the feces should be made over and over again.
  • Second, carriers must be told of their condition. They must be taught to use precautions against soiling the hands with the excretions. They must be taught to wash their hands frequently: always after leaving the toilet and always before handling food; they must never handle the food of others and they must try to give up the senseless habit of shaking hands.

We should all be careful to avoid eating uncooked food which has come in contact with the hands of persons whose history is not known to -us and who may have contaminated the food immediately before our getting it.

Those of us who have had typhoid fever should be examined to determine whether we are carriers. If we are carriers, our families should be inoculated against the particular strain of the typhoid germ which infects us and special precautions should be exercised against the transmission of the bacilli in the household.