Influenza

“ Our common epidemic influenza or grip, occurring practically isolated or in very small outbreaks, belongs to the same type of disease as the pandemic variety, but is due to a mitigated form of the causative organism, one of decreased virulence and of shorter viability. ”

“ THE BACTERIOLOGY OF THE 1918 EPIDEMIC OF SO-CALLED INFLUENZA. The epidemic disease known as influenza is believed to be due to an undetermined organism which causes an infection that lowers the resistance of the body as a whole, and of the respiratory organs in particular. This allows the invasion of other pathogenic micro-organisms. The most important complicating infections are due to the influenza bacilli, different strains of pneumococci and different varieties of streptococci. Some careful observers regard certain of these organisms as the primary cause. ”

“ I have no doubt that a historian who during the 1918 epidemic of influenza might have limited his observations entirely to the disease as it occurred at Camp Sherman, Ohio, and who saw 125 robust soldiers dying each day, would have truly written that the disease killed off the soldiers murderously. ”

“ Droplet infection and spread through inanimate objects.—The actual mode of spread of the virus of influenza from one individual to another is unknown. The more generally accepted explanation is that the infecting agent leaves the body through the respiratory tract, usually in the spray of coughing or talking; contagion is by droplet infection, as is sometimes the case in other respiratory infections. Thorne and others have called attention to the capillary congestion of the conjunctivae very early in the disease. ”

“ B. LESIONS OF THE LUNG In the prosecution of the scientific study of any disease, the great temptation is to differentiate its various manifestations with the intention of elaborating a classification. While there may be more or less distinct types of pulmonary involvement in influenza, so many intermediary forms appear in an extensive series of cases, that any classification must necessarily be arbitrary. ”

“ More persons have died of the influenza in the present year than died of the cholera when it raged in 1832; but then a vastly greater number have been affected with the one disease than with the other. ”

“ General Manner of Spread in Individual Localities. Having discussed the mode of propagation of influenza among individuals we will follow the disease as it attacks one person after another in a community and study the epidemiologic picture, drawn no longer with the individual as a unit, but with the community as the unit.
We must here distinguish between a primary epidemic, the first wave of a progressing pandemic, and the secondary type in which may be grouped those large or small recurrences which light up for a period of one to three or more years after the primary wave. ”

“ These are important indications for the pathology of influenza in general. They point to its inclusion in that strange class of infections which fall most upon a population, or upon those orders of a population, who are the least likely to breed disease by anything that they do or leave undone. ”

“ The most important feature with reference to influenza in children is its very active tendency to develop complications. These complications generally affect the respiratory tract. So we find in children suffering from grippe an easy disposition to get bronchitis or broncho-pneumonia. The younger the child the greater the danger.
The disease itself, so long as it remains an uncomplicated influenza, is not of much importance or severity. The lesson to be learnt, therefore, is to treat the disease with respect and take every precaution to avoid the possibility of developing a complication. ”

“ Up to the present time we have discovered no one characteristic by which we may say that a case or an epidemic is positively influenza. We have had to rely on the general symptomatology, which indeed is sufficiently characteristic, although so nearly like the symptoms of certain other diseases as to make us hesitate to make an absolute diagnosis, and on the epidemic characteristics. The necessity of an absolute criterion in the clinical diagnosis is particularly felt in the presence of an isolated interepidemic case, or a small endemic outbreak. ”

“ It is well known that influenza is an infectious disease, which rapidly spreads through the family and the community, but it is not so well known that the so-called “common colds,” ordinary sore throat, and tonsillitis are also highly contagious. The infection is carried from one person to another by direct contagion; the air is being constantly sprayed with the germs of disease in talking, laughing, sneezing, and coughing. ”

“ The Butler is feeble. Crossing the parquet he is down with a dish. In another hour he is down with—shall we begin to say—Influenza? I thought Influenza was sneezing and coughing and the most violent of colds. Yet I hear very little of that in the house. I shall pack up and leave to-morrow morning. Sharp pain in back as I stoop over portmanteau. Feel queer in head. Pains all down my legs. ”

“ Influenza is described as a disease with distinctive epidemiologic characteristics, the chief of which are found only in epidemic spreads. Thus one of the fundamental characteristics of these epidemics is supposed to be the primary type of wave, the wave characterized by rapid rise, quasi-symmetrical evolution, and a concentration closely grouped around the maximum. “This is found in no other disease. In no other type of epidemic does the curve rise as rapidly to a peak or fall as swiftly, nor is the epidemic completed in as short a time.” ”

“ In no case was any exceptionally cold weather, intercalated in the period of the epidemic, accompanied with an increase of deaths from influenza, or even with an arresting of the downward course of the curve of mortality, if the cold occurred at the time the epidemic was on the wane. Other diseases which appear to have prevailed most extensively during epidemics of influenza are diseases of the breathing organs, phthisis, diseases of the circulatory system, rheumatism, and diseases of the nervous system. ”

“ The liability to contract influenza, and the danger of an attack if contracted, are increased by depressing conditions, such as exposure to cold and to fatigue, whether mental or physical. Attention should, therefore, be paid to all measures tending to the maintenance of health. Persons who are attacked by influenza should at once seek rest, warmth and medical treatment, and they should bear in mind that the risk of relapse, with serious complications, constitutes a chief danger of the disease. ”

“ Cases of illness occurring during the months of 1918 and 1919 in which influenza was epidemic and in which the patient remembers that he had the more definite symptoms, (fever, headache, backache, pain in the extremities, pneumonia) and in which he was sick at least three days and in bed at least one day, have been designated as “Yes.” The symptoms chosen are those most likely to be remembered. The individual frequently does not remember all. Statements of the absence of fever are often unreliable. ”

“ One attack of influenza does not seem to be protective against another; the disease in this respect resembling diphtheria, erysipelas, and cholera rather than smallpox, measles, or whooping cough. The duration of the epidemic in a locality is so short that it is difficult to distinguish between second attacks properly so-called, and relapses, which are frequent enough. A case is recorded in the ‘British Medical Journal’ of February 15, 1890, in which a patient who had suffered from influenza in France in December, 1889, had another attack in England in January, 1890. ”

“ The manner of spread of epidemic influenza is constant in a primary epidemic and the epidemic as a whole has certain features which render it characteristic. The sporadic case has as a rule the same quite clear cut clinical symptomatology, but it fails to manifest the one feature most characteristic of epidemic influenza—a high degree of contagiousness. ”

“ There seems to be some basis for the supposition that a group of individuals exposed to an attack of influenza displays within the succeeding 207three months, or slightly longer, a relative general group immunity. If the group be considered as a whole those even who did not develop the disease previously appear to have become less susceptible. ”

“ Finally, all measures, of whatever kind, that tend to depress the general nervous system or the functional activity of the respiration, and especially the heart-power, are to be sedulously avoided in the management of influenza. During the convalescence unfavorable influences of the weather are to be guarded against. It is important to warn the patient that a severe attack of influenza renders him liable for some time afterward to pulmonary disorders. ”

“ The sudden onset of influenza, its not infrequent abrupt termination, which suggests crisis, its unsparing seizure of great numbers of the population, the severity of the nervous symptoms, and the amount of laryngo-bronchial irritation, often out of measure with the lesions of the mucous membranes,—all point to the action of a morbid agent affecting the body at large. ”

“ Opinions of all observers who have studied in detail the question of immunity in influenza are remarkedly in accord. The conclusions reached by Parkes in 1876 are valid today, and form as excellent an abstract of our present knowledge as any produced since his time. “There is some discrepancy of evidence, but, on the whole, it seems clear that, while persons seldom have a second attack in the same epidemic (though even this may occur) , an attack in one does not protect against a subsequent epidemic. ”

“ The disease spoken of as influenza in the horse has many other names. It is commonly called pink-eye, shipping fever, stable pneumonia and bronchitis. By some influenza is not believed to be a single disease, but a group of diseases. By others it is considered to be a definite entity, varying in its symptom complex at different times and with various horses. Infectious laryngitis and infectious pharyngitis seem to be independent diseases. ”

“ Complications, chiefly of the respiratory tract, as a rule occur in such a large proportion of individuals that they very nearly dominate the picture. Although caused by various microorganisms, all of which appear to be secondary factors the results are so characteristic that in the past, descriptions of influenza epidemics have usually been descriptions of the complications of epidemic influenza. Most influenza epidemics are complicated. ”

“ 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. ”

“ Just now every one is anxious about her, for she is daily expecting a small addition to her family, and is exceedingly ill with influenza—a very violent form of which has recently broken out, severely affecting lungs and throat. It is a real epidemic. ”

“ The treatment of influenza is expectant and supporting. Not only is the epidemic self-limiting, tending to exhaust the susceptibility of a community, in most instances, in the space of a few weeks, but the attack is also of definite duration, and the perturbations set up by the action of the influenza-poison upon the individual subside spontaneously in three or four, or at most ten or twelve, days. ”

“ Deaths resulting from influenza are commonly due to pneumonias resulting from an invasion of the lungs by one or more forms of streptococci, or by one or more forms of pneumococci, or by the so-called influenza bacillus, or bacillus of Pfeiffer. ”

“ In considering the effect of influenza on the death rate in general, and in considering the relationship of influenza to other diseases in 116general, it is important to distinguish those diseases which are apparently unrelated and those diseases which occur as direct complications or sequelae. Bronchopneumonia, bronchitis, empyema, otitis media, frequently tonsillitis and sometimes erysipelas, occur as sequelae. Meningitis should frequently be included in this group. ”

“ Determining why susceptibility to a special disease in a particular case exists will constitute the greatest line of advance for the understanding and prevention of disease, and so the perfection of public health. In the last influenza epidemic countless physicians were puzzled by the spectacle of men and women in the pink of condition carried off in twenty-four hours while puny associates were either passed over, or pooh-poohed their colds. Pathologists have spent their energies fruitfully upon the infectious causes of disease, the microbes and parasites especially. ”

“ An individual in bed two days, but sick for three weeks might be recorded as average. A mother, with a family of sick children and who spent no time in bed may have been a severe case of influenza. In fact, we have allowed ourselves a certain latitude in individual cases in classifying both the diagnosis and the severity of the disease. ”

“ There have been many examples reported from personal experience to show that influenza is transmitted from man to man. Two objections, however, have had to be met, before this view was generally accepted. First, it has been claimed by some that the disease spread more rapidly from an assumed focus than individuals could travel, and second, that instances were on record of cases occurring spontaneously in isolated communities. ”

“ Whenever doubt exists as to the nature of the disorder, a microscopic examination of the expectoration or of the mucus from the throat by a competent physician will definitely determine the existence of influenza, if the special germs of that disease are found. It is the prevailing and erroneous fashion for a person to call any cold in the head the grippe; and there are, indeed, many cases in which it becomes difficult for a physician to distinguish between grippe and a severe cold with muscular soreness and fever, except by the microscopic test. ”