INFECTIOUS DISEASES IN GENERAL HOSPITALS: THEIR PROPER CONTROL FROM THE STANDPOINT OF SANITARY SCIENCE.

ROBERT J. WILSON, M.D.,

Superintendent of Hospitals, Dept. of Health,
City of New York.

Before entering into the discussion of the specific considerations of this paper I desire to call your attention to some of the general priciples of immunity and conditions governing the spread of infection. We consider immunity to be a resistance to disease, which may either be natural or acquired. If natural, the condition is due to protective substances in the blood, which either prevent the multiplaction of infecting organisms or neutralize their poisons as rapidly as produced, or the infecting organisms produce no poison. to which the infected animal is susceptible. If immunity is acquired it may be through the production of specific protective substances by the cells of the infected animal (due to stimulation of these cells by the infecting organism, or organisms closely allied to it, or by substances conttained in its body), or by the injection of specific protective substances produced in the body of some other animal. In the first instance we have active immunity due (a) to recovery from disease; in this case the protective substances are produced by the cells of the patient, through the stimulation of the infecting organism; (b) through vaccination with living. organisms, or (c) inoculation with dead ones, as in the case of opsonins. In the second instance we have passive immunity conferred by the injection of antitoxin.

In considering the proper care of infectious diseases we are always influenced by, these problems of immunity.

Natural immunity, except in dealing with diseases of domestic animals, is a negative factor; for we do not know, nor is there any way of our ascertaining, whether it exists or not. But in the case of acquired immunity the conditions are quite different. If active immunity can be conferred we know that we must wait a reasonable time after vaccination for the protective substances to be produced, before we can expose the immunized person, with safety to the disease, as in the case of successful vaccination against smallpox. On the other hand, when passive immunity is conferred by the use of antitoxin, all of the protection we expect to get, immediately follows the injection, and in a ward or dormitory filled with persons who have been thus protected we can expect that the immunized persons will not suffer any ill effects of infection from the organism against which they have been immunized.

Fully as important as the question of immunity in those. cases where we have knowledge of the infecting organisms, and more so where we do not, is that of conditions governing the spread of infection. Scientific research has taught us that the organism must be virulent (able to produce poisons) and that a considerable number must be introduced into an animal before infection takes place. From this we may know that prolonged exposure to a case of infectious disease is more liable to spread the disease than if the infectious case is immediately placed in isolation; a fact that is frequently overlooked by hospital authorities while awaiting a diagnosis.

My rule is to isolate on suspicion and make the diagnosis after isolation. This precaution may save spreading the disease from one to many cases, from the simple reason that not a sufficient amount of infectious material has been allowed to escape in the ward to produce infection.

In addition to the quantity of infectious organisms thrown off we must remember their ability to resist deleterious influences such as drying, exposure to sunlight and the like. Organisms producing spores such as tetanus or being protected by the nature of their protoplasm such as tubercle bacilli must ever teach us the necessity of thorough cleanliness and disinfection. The recurrence of infection in supposedly disinfected surgical wards is an example too commonly known to call for further illustration.

With these general features in mind let us proceed to the specific considerations of this paper.

For convenience of discussion I shall give to terms used in the title the definitions as I interpret them. By infectious diseases is meant all diseases due to microorganisms, the biological characteristics of which are known, and whose presence in the afflicted animal gives rise to definite diseased conditions, the disease usually having the name in part or in whole of the infecting organism. In scientific research contagious disease simply represents a certain infection. In this paper we consider certain infectious diseases which by the general practitioner and clinician are known to be communicable, but are quoted under the general term infectious diseases, for convenience of discussion. In this class of diseases the most prominent examples are: Tuberculosis, Pnuemonia, Epidemic Influenza, Typhoid Fever, Dysentery, Cerebrospinal Meningitis, Diphtheria, Erysipelas, Gonorrhoeal Vaginitis, etc.

By general hospitals is meant hospitals that admit for treatment every kind of cases not classed as purely contagious or of unusual communicability, such as pest, cholera, yellow fever, etc. By control is meant the ability to isolate, properly care for and prevent the spread of infection from a single case in a restricted area and to sterilize such area after the termination of the case. By sanitary science is meant the facts learned by scientific investigations through biochemical and physiological laboratories and through comprehensive studies on the transmission of diseases, as for example in the caes of yellow fever and malaria.

Is it for the best interests of all in a general hospital to admit into it patients with communicable diseases? This can positively be answer in the affirmative if the proper precautions are observed in their care, and the people in charge of them are familiar with the life history and habits of the infecting organisms.

Now let us consider briefly the most common infectious diseases usually cared for in general hospitals.

Tuberculosis. Almost every medical attendant and nurse now knows more or less of the life history and habits of the tubercle bacillus. They are aware that this organism may live for a long time outside of the body under favorable conditions, in dust and refuse if

not exposed to the direct rays of sunlight; they know that after infection the tubercle bacillus may lie dormant for a long time in a lymphatic gland before the disease actively manifests itself; they know that the organisms are thrown off from the body mostly through the sputum and excreta, and lastly and of most importance of all they know that the disease is only communicated through inoculation with the tubercle bacillus. With these facts ever in mind, and following out explicitly the instructions of scientific workers in tuberculosis, this disease can be taken into a general hospital without fear of its spread and to the best interest of the afflicted persons without prejudice to other inmates. It is to be understood that tuberculosis in a general hospital is to be kept in wards to itself and that the food, left over after meals is not to be returned to the diet kitchen, and that the laundry of such a case is to be sterilized before being sent to the hospital laundry for washing, and that the hygienic care of the ward or of a single case is to be that now generally adopted in hospitals for this disease.

2. Pneumonia.-As in the case of tuberculosis, here we have a disease with whose exciting factor we are well acquainted. The frequency with which the pneumococcus is found in the throats of healthy persons does not warrant us in the belief that we can with impunity place cases of pneumonia in general wards. We must remember that the pneumococcus of clinical pneumonia is of great virulence while those in normal throats are non-virulent, or the person whose throat is so invaded is not susceptible to the disease. But in many of our institutions we put these cases in general wards between beds of patients suffering with some disease not communicable and believe that we are treating our patients with fairness.

It has been shown that in pneumonia for a considerable time after the patient has coughed and expectorated, the atmosphere immediately surrounding such patient is filled with suspended particles containing the living organisms, a fact not to be lost sight of by attendants for their own protection, as well as the protection of patients closely adjacent to it.

It has been my fortune to see cases of diphtheria that seem to be particularly susceptible to pneumonia develop this disease with remarkable rapidity, the disease spreading from bed to bed throughout a ward. And I have seen the ward reconstructed with each bed standing in its separate stall, with the effect that the spread of pneumonia from bed to bed as was formerly the case has now been almost wholly checked. It is possible that the use of respirators, if not inimical to the patient, in certain instances would keep the area immediately about the patient fairly clear from pneumococci.

3. Epidemic Influenza.-How many of us have seen influenza admitted to wards, and have noted the great rapidity with which it has spread from bed to bed and ward to ward, until the whole hospital has been infected. I have recently been told by a scientific worker that this was non-preventable. I do not personally believe it and if confronted in the hospitals under my own charge with an epidemic in the community, would try by careful isolation to keep it out of our sick wards; this would mean eternal vigilance, which is the only way to deal with communicable diseases under any circumstances.

4. Diphtheria.-While classed with contagious diseases and usually considered of great communicability, this disease on account of our thorough knowledge of its etiological factors and how to prevent its spread, can be held in a general hospital without fear of an epidemic following a single case. Isolation and immunization are the conditions that prevent its spread. On account of the cost of properly caring for it, and the lack of experienced intubators it seems advisable to confine this disease to hospitals built for its special care.

5. Typhoid Fever. The infecting organism of typhoid fever being eliminated almost entirely through the excreta and the care of the most careless attendants to prevent their hands being contaminated with these discharges probably accounts for the slight spread of this disease from patients to those who have the care of them. But we all know how easy it is to get a