Synonyms:—Yellow jack; black vomit; febris flava.
Definition:—An acute highly infectious, epidemic and endemic disease, characterized by an abrupt period of invasion, followed by a remission and that by a relapse. Also by a high fever accompanied by a yellowish discoloration of the skin (often mottled), frequently by oozing hemorrhages from mucous surfaces, and by a black vomit. It is indigenous to America and is common in the sub-tropics and tropics of this country. It has a most interesting history.
Etiology:—This disease prevails during the middle and late summer months and is abruptly terminated by frost. Whites are more readily affected than blacks, and children and males, than females. A specific organism called the bacillus icteroides is found present in this disorder, which is readily conveyed by the mosquito, although this is probably only one means of infection. The mosquito must bite a sick person and thus become infected. A bite from the mosquito after twelve days will convey the disease to an individual not rendered immune by a previous attack. The disease is not conveyed by fomites, consequently disinfection is not essential. Cleanliness, however, and good hygienic surroundings are all important.
Symptomatology:—There are usually three distinct stages to this disease. For a few hours only before the abrupt onset of the disease, are there any prodromata. These are malaise, some lassitude, vertigo and headache. The rigor is sudden and unannounced, and with it there is pallor, severe muscular pains, especially in the back, and with the headache, which is usually very severe, there is pain in the eyes, and much distress in the stomach. There is a rapid rise in the temperature to 104.5° or even 106° F. within twenty-four hours. This usually persists for two or three days, although in the mild cases there will be a fall of the temperature within a few hours. When the fever persists there are slight morning and evening remissions until the end of the third day, when the remission in the fever is marked and all the phenomena abate, the pulse remaining abnormally slow. There are, however, marked evidences of serious impairment of health, and at this time the characteristic jaundice—the yellow or bronzed condition of the skin and conjunctivae—appears, which is pathognomonic of this disease. If all conditions are favorable and if the previous course of the disease has not been too severe, the patient may recover from this point.
After one day perhaps, or a little less or more, there is a recurrence of all the symptoms in greatly aggravated form. Exhaustion occurs with signs of collapse, the temperature may rise even beyond its previously highest point (secondary fever), or it may fall below normal and the skin become positively cold (the algid form), with a rapid and compressible pulse, increased gastric distress, and the vomiting of, at first, a clear liquid in which float reddish or brown flakes which increase in quantity and color until it assumes the character of well known black vomit.
Hemorrhage may occur from the stomach and unchanged blood may appear in the vomit. Or passive hemorrhages may be general from all mucous surfaces or even from the skin. With these serious symptoms an abatement and a change for the better may occur, but this is rare. There is usually a suppression of urine more or less complete, with serious depression rapidly approaching collapse, hiccough, the so-called "Hippocratic" facial expression, subsultus tendinum, coma and convulsions, which may be of uremic origin, and death. The urine of yellow fever is often albuminous from the first, and this is considered a positive evidence in the diagnosis. The quantity is lessened at the onset and often decreases to final complete anuria.
There is a wide variation of symptoms in this disease. The course above outlined is most common, the three stages being distinct. But the course may be different in individual cases in a given epidemic. Or an entire epidemic may assume peculiarities of manifestation. The algid form may predominate, in which there is sub-normal temperature and no secondary fever, or there may be a type designated as apoplectic, in which extravasations within the tissues of the brain occur early, with dulness increasing to coma and paralysis or convulsions. In still another form the symptoms of cholera are so marked as to render a correct diagnosis extremely difficult.
Diagnosis:—When there is as yet no prevailing epidemic of this disease, an exact diagnosis may be extremely difficult. When an epidemic is declared the sudden onset, the intense backache, the pain in the eyes, and after perhaps forty-eight hours the marked slowing of the pulse while the temperature is yet very high, arc characteristic. In the period of remission the jaundice will determine the diagnosis, and later the black vomit, with increased jaundice and suppressed urine, are unmistakable evidences.
The facial expression is of great assistance in diagnosis, to those familiar with the disease. The extreme flushing of the face and the intensely injected and jaundiced eyes, are characteristic.
The early development of albuminuria will be of assistance. Remittent fever is milder, has regular daily remissions and no black vomit. The disease in isolated cases is mistaken for dengue especially; also for relapsing fever, and for pernicious malarial fever.
The latter has protracted chill, early remission, no albumin, no vomit. Relapsing fever has the spirillum of Ober-meier in the blood, enlarged spleen, but little jaundice, no vomit, and no initial albuminuria. Dengue is characterized by the extreme bone pains, the marked remission and the eruption.
Prognosis:—The mortality varies in different epidemics; some are light, some virulent. In severe cases with no improvement in the second stage, the prognosis is bad, as from thirty to forty per cent die. In virulent epidemics the mortality has been as high as eighty-five per cent. A larger number of men are attacked, and less blacks than whites.
Treatment:—Specific measures in the treatment of this disease have not been determined. If the various indications are met, they must be positively met, with full dosage of the remedies. Sternberg advised the bicarbonate of soda in large, full and persistent quantities in all cases during the course of the disease. The method has not been sustained, although its benefits are not questioned. The facial symptoms suggest gelsemium in full and persistent doses. Iris, chionanthus or chelidonium should be given early to retain and sustain the normal action of the liver. The organ should not be overstimulated. The bowels should be moved early with laxatives that in no way irritate the stomach. At the onset, hot mustard baths, persistent foot-baths and counter irritation over the spinal cord will be found of benefit. When albuminuria appears, dry cups should be applied over the kidneys, and subsequently persistent heat, especially when the pulse begins to run slow. On the first and second day of high fever cool sponging may be resorted to. Much benefit will be derived after the second day from mild iced infusion of capsicum, which should be continued to nearly the end of the first stage of the disease. The infusion should then be given hot through the second stage. This will relieve hiccough should it appear. If a drop or two of carbolic acid or creosote be dropped into and dissolved in this and taken three or four times daily it will soothe the irritation of the stomach and in part control the vomiting.
In the remission, gelsemium and quinin together will be found of much service in full, large doses. Heat to the kidneys must not be neglected. The urine should be examined daily and uremia anticipated and combated. Early exhaustion and heart failure will be met promptly with cactus, avena sativa in the hot capsicum infusion, and strychnin arsenate. At any time when sudden exhaustion threatens, especially during the third stage, the physiological salt solution should be introduced into the colon, hot. If the exhaustion be extreme, hypodermoclysis should be resorted to.
The feeding of these patients must be most carefully conducted. Milk to which is added a little lime water or soda, or milk predigested, will be sufficient for the first two days. It may be given iced or ice cream will be acceptable in some cases when the temperature is high. The white of an egg thoroughly beaten and dissolved in water and seasoned with cinnamon is acceptable. Fruit juices or dissolved jellies to which a little infusion of capsicum is added will sustain the strength of the patient. Rectal enemata of stronger diet may be resorted to at times. During convalescence the diet may be increased by eggnog, and later by very soft boiled eggs, beef tea from beef extract, hot broths, and toast.
The patient must lie quiet in bed in a properly ventilated room, and annoyance of every kind avoided. The bed pan must be used throughout the disease and through early convalescence, and the discharges must be disinfected. The patient must not arise from the bed until much strength has been regained, and especially until the weakened heart muscles have been restored. During this latter period phosphorus, nux vomica, strychnin, hydrastis and iron may be given with satisfaction.
During the course of the disease, indications for echinacea, polymnia uvedalia, iris or lycopus may occur, as well as for baptisia and dioscorea. Echinacea may be given from the first with gelsemium, aconite or bryonia. If it be continued in from ten to fifteen drop doses throughout the entire course of the disease, there is no doubt that favorable results will obtain, especially if blood infection, uremia, and nervous phenomena therefrom are apparent. Belladonna or frequently repeated small doses of atropin will be indicated in some cases at the end of the first stage, and if given in sufficient dosage will sustain an equalized circulation and will tend to prevent cerebral congestion and congestion of the glandular organs.