Influenza

by Warren T. Vaughan

What instructions can we give to the individual for his own protection? There are at least six precautions based on scientific knowledge. They are:

First: Avoid crowds. Second: Avoid crowding in the family. Third: Sleep alone. Fourth: Pay particular attention to personal hygiene. Fifth: Boil all dishes, etc., after meals. Sixth: Do not eat in insanitary restaurants. Eat at home.

Should cases be isolated? Should they be quarantined until no longer infective? The experience of the last epidemic has rendered us pessimistic. We have found that isolation and quarantine does little or no good. Institutions which were held under rigid quarantine for the first months of the epidemic were later invaded when discipline became lax. The disease thereafter spread often as extensively as it would have, had there been no delay. But, on the other hand, there is record of some institutions in which the quarantine lasted throughout the epidemic and in which the inmates never became ill. All of our past experience with infectious diseases leads us to believe that isolation of cases should be enforced. The experience of 1918 should not cause us to change from this point of view. Up until now the procedure has been without results. It has been nearly impossible to enforce it. Further study must be made before any definite conclusion can be reached.

The same in general may be said regarding disinfection after recovery of a case of influenza. Today most people believe that disinfection is unnecessary. The work of Lynch and Cumming, if correct, would indicate the contrary. The possibility of transmission through inanimate objects has not as yet been completely eliminated.

The efficacy of face masks is still open to question. Certainly the face mask as extensively used during the 1918 epidemic was of little benefit and in many cases was, without doubt, a decided detriment. The same mask was worn until it was filthy. It was not worn in such a way as to be a protection. Even had the nose and mouth been efficiently protected, the conjunctivae remained unprotected. The work of Maxcy and of Vincent and others has demonstrated the importance of the naso-lachrymal duct as a possible portal of entry into the respiratory tract proper. After cultures of Bacillus prodigiosus were sprayed upon the ocular conjunctivae these organisms have been recovered from the nose within five minutes, from the nasopharynx within fifteen minutes and from the feces within twenty-four hours. One difficulty in the use of the face mask is the failure of co-operation on the part of the public. When, in pneumonia and influenza wards, it has been nearly impossible to force the orderlies or even some of the physicians and nurses to wear their masks as prescribed, it is difficult to see how a general measure of this nature could be enforced in the community at large. If masks are to be used they should be employed in the same manner as for protection against the plague. They should be made to cover the entire head. This procedure has been recommended particularly by Vincent and by Thorne.

It is safe to say that the face mask as used was a failure.

Problems for the future. Constructive research.—While pure epidemiologic study of influenza will not demonstrate the causative agent, it is the chief procedure upon which we can at present rely for improvement in our methods of combat. Many important laboratory contributions have been made during the last two years. The majority have been without immediate value to the health officer. The author suggests in the following paragraphs a plan of study, based upon past epidemics and the experiences of the last pandemic, as epitomized in the preceding chapters. During the exposition of this subject we have drawn certain conclusions and have developed some theories. We believe that they explain the facts correctly, but should the hypotheses prove not entirely correct the value of the following outline for study will be in no way impaired.

To become thoroughly acquainted with epidemic influenza in all its manifestations would require a life time of study. Knowledge of the disease would be greatly furthered if competent epidemiologists should see fit to devote their entire time to a study of the disease in its various ramifications. The author suggests a research organization of individuals whose function it would be to become completely acquainted with influenza. The organization should be under the direction of a competent board of epidemiologists. Under them would work several groups composed of epidemiologists, bacteriologists and others. There should be sufficient groups so that they might be distributed to diverse regions of the earth. They should be equipped for travel, with mobile bacteriologic laboratories and all the necessary equipment for epidemiologic surveys, so that at a moment’s notice they could proceed to wherever an epidemic of any disease simulating influenza is reported to be prevalent. The working groups would be under the administrative control of the central directors and would make their reports to them. All groups should be so distributed geographically as to have easy and rapid access to any community in which an epidemic might occur. They would keep themselves informed concerning the disease prevalence in all communities under their jurisdiction. This would be done through the co-operation of the civil health authorities and through the utilization of all other available sources of information. The central board should be constantly in touch with the groups, so that the infectious disease prevalence in all parts of the world would be known at all times.

Had such an organization been in existence during the last thirty years, every one of the so-called influenza epidemics reported in one place or another would have been investigated. Detailed epidemiologic, statistical, demographic and bacteriologic reports would have been made. It matters little how small or insignificant the outbreak appears to be. Even the smallest have their characteristic features and are worthy of study. If we study epidemic influenza but once in thirty years, we will never become well acquainted with the disease. We must see it repeatedly and frequently. If it does not exist during the intervals we must study the diseases simulating it. It is surprising how much of the knowledge acquired in 1889 was forgotten by 1918. Even some of the more important features had passed from memory. Thus we find statements in 1918 that the age morbidity was quite different from that in all preceding epidemics. Research into the literature of the past does not corroborate this impression.

If influenza is scattered throughout the earth in mild form, it would avail us but little to send a commission to Bokhara to study the endemic focus supposed by some to exist in Turkestan. Even though the disease were endemic in that country, one would not expect to discover epidemics there. The general immunity of the population in the endemic area is probably increased. Nevertheless one unit might well be stationed in Turkestan, there to study the existing conditions regarding infectious diseases.