Re: WHO warns of severe form of swine flu
It seems to be pretty much similarities about lung pneumonia, and other symptoms (from the posted Snowy's thread link text informations), in which some doctors analisy descriptions seems to point to a possibility of stil a same agent but with diferent severity cases manifesting (descriptions in pandemic 1918 spring and fall wave):
The Snowy's thread link:
http://www.flutrackers.com/forum/showthread.php?t=12911&highlight=excess+mortality
Disease Pattern just Previous to 1918 Pandemic
Snowy's POST #13:
INFLAMMATORY DISEASES OF THE RESPIRATORY TRACT (BRONCHITIS, INFLUENZA, BRONCHOPNEUMONIA, LOBAR PNEUMONIA)
PART XII
CERTAIN CLINICAL ASPECTS
(EXCERPT - sympt./pneumonias species/throat/...):
...
The pneumonia of this period was carefully studied by a special commission of medical officers working at Camp Travis, Tex.<sup>2</sup><sup> </sup>They noted the presence at the time of an "epidemic of coryza, laryngitis, and mild bronchitis" in both the civil and military population of San Antonio.
The report of the commission states that clinically the pneumonias studied could be divided into three groups:
Bronchopneumonia, associated as a rule but not invariably with a recent measles attack;
(2) lobar pneumonia, giving the familiar signs and symptoms of that disease and sometimes following measles;
(3) a group showing clinically and anatomically a combination of groups 1 and 2.
The description of the bronchopneumonia found there is of especial interest not only because it was the unusual feature of the outbreak, but because it is of value in comparing it with the bronchopneumonia of later waves.
The cases at San Antonio were nearly all associated with the hemolytic streptococcus, though nearly half of them showed the presence of the Pfeiffer bacillus as well.
Onset was gradual and without definite chill or sudden elevation of temperature, whether occurring during the course of measles or only after an interval of several weeks. The temperature rarely exceeded 104° F., and was frequently irregular even in the absence of empyema. The pulse rate was not extremely rapid even in cases near death. Respiration, too, was not extremely rapid but was characterized by extreme respiratory difficulty.
Cyanosis was constant even in early cases.<sup>a</sup>
The cough was troublesome and the sputum varied in character, though not showing the tenacious rusty type, typical of lobar pneumonia. Pain was usually marked and was associated with the frequency of pleural infection. When noted, consolidation was usually at the base.
Râles, musical, squeaking, or moist, were usually heard throughout the chest. In some cases characteristic signs of consolidation in a certain area persisted for a few days and then entirely disappeared. In uncomplicated bronchopneumonia, wide areas of dullness and tubular breathing were never observed. When such signs were found there was invariably a concurrent lobar pneumonia. Empyema complicated about one-half of the cases studied and its fatality was at least 50 per cent.
The lobar pneumonia studied showed the presence of pneumococci, the epidemic types being demonstrated in two-thirds of the cases. In the series showing combined lesions both pneumococci and streptococci usually were demonstrated.
During the 1918 spring epidemic, pneumonia was for the first time attributed to antecedent influenza in any considerable number of cases, although the diagnosis previously had been made.
_____________________________________________________________________________________________________________________________________
The clinical types of pneumonia seen in March and April corresponded well with those seen in the camps showing a high death rate during the winter months.
_________________________________________________________________________________________________
<sup>a</sup>Other observers have stated that cyanosis on admission for measles characterized cases that developed pneumonia later.
<hr size="1" noshade="noshade">
At this time the camps were much more generally affected. Empyema was still common and the mortality was generally associated with this complication. A small number of cases of a new type of the disease was seen for the first time during this outbreak.
A patient with an attack of typical influenza of two or three days’ duration would, after a day or two of normal temperature, develop acute pneumonic symptoms and die within 48 hours. This was the fulminant type of influenzal pneumonia familiar in the fall outbreak.
The proportion of cases recorded as lobar in type was lower in the spring than in the winter and the case fatality of pneumonia was higher.<sup>78,</sup><sup>79</sup>
<sup>
</sup>
During the period of lower incidence of respiratory infections following the spring outbreak and
lasting throughout the summer, this increased case fatality of pneumonia cases persisted and even increased as is seen in the monthly tables. The increase culminated in the month of September, 1918, with the violent outbreak of the most severe influenza wave, which first showed its great virulence in the northeastern camps.
The percentage of influenza cases developing pneumonia at this time varied in different localities. The maximum figures were about 25 per cent. The usual case fatality at this time was around 30 per cent.
Though the disease, as seen in different camps, varied somewhat in its clinical manifestations due to the various factors that have been discussed, the general characteristics of the complication were very constant.
Few observers were able to distinguish clinically with any definiteness in the early stages of the disease between cases which showed later lobar lesions and cases of bronchopneumonia.
The following condensed description of influenzal pneumonia of the most fatal type is drawn largely
from a series of studies made at the Walter Reed General Hospital, D. C.<sup>82,86</sup>
<sup>
</sup>
The onset of the pneumonic complication occurred either after two or three days of normal temperature following an attack of influenza, or it developed gradually without there being an afebrile interval. In the former group the onset was often characterized by chill and sudden rise of temperature.
The severity of the disease was correlated with the amount of lung involvement, unilateral cases doing much better than those with both lungs affected. Fulminant cases with severe toxemia showed rapid involvement of the entire lung.
In nonfatal cases, usually presenting a unilateral lesion, the temperature ranged from 100° to 103° F.
The pulse was characteristically slow; the blood pressure low, the systolic figure often below 100 mm.; respiration was only slightly accelerated. Nonfatal cases usually recovered after an illness of about a week and defervescence was by crisis in some series, by lysis in others. In cases with bilateral lesions the cyanosis was more marked, even to an indigo blue color, the temperature ranged somewhat higher than in the unilateral cases and often showed variations paralleling the advance and recession of the pulmonary lesion as shown by the X ray or by physical signs.
Cough was frequent and exhausting; the sputum, blood tinged or mucopurulent. In the more toxic cases, terminating fatally, the color of the patient from the first was either that of an intense cyanosis or a muddy, claylike pallor. The pallor was of particularly bad prognostic import. Nervous symptoms appeared early, restessness and delirium being marked.
<hr size="1" noshade="noshade">
The respiration became very rapid and dyspnea was pronounced. Physical signs of irregular consolidation and of edema filled the entire chest. The temperature ranged to 105° F. or higher, and death occurred in from three days to a week.
It is evident that these groups were not clean-cut and that all degrees of varying severity intervened. Inasmuch as such a proportion of severe pneumonia has in the past seldom been associated with influenza, it is important to record in somewhat greater detail the peculiarities of this outbreak.
The first point to strike the observer was the universal occurrence of cyanosis. This condition appearing in an apparently uncomplicated case of influenza, if of a degree at all marked, usually presaged the onset of pulmonary inflammation. Whether due to toxic changes in the composition of the blood or to mechanical interference with oxygenation by the exudate in the lungs, the intensity of the cyanosis was, in general, an index to the severity of the case.
In milder cases of influenza, a peculiar shade of "pink cyanosis" was observed, an erythematous flush of an unusual shade. The well-established case of pneumonia showed a shade that was usually described as heliotrope, and in the most asthenic group, usually associated with coma vigil, a muddy clay-colored pallor prevailed.
In some series of cases the tendency to hemorrhages from the mucous membranes was very notable. Epistaxis, which occurred in 10 per cent or more of the cases, was of all degrees, but often severe, recurrent, and debilitating in the extreme. Purpura, intestinal, and renal hemorrhages also occurred.
Of respiratory symptoms proper it may be said that these differed relatively little from the respiratory symptoms of the usual pneumonias.
Pleuritic pain was frequent, cough was distressing, and frequently there was so much expectoration as to make resorting to narcotic relief seem dangerous.
The character of the sputum varied from the tenacious rusty expectoration of typical lobar pneumonia, through varying degrees of mucopus, and frothy blood-stained material to the profuse pink froth in the mouth and nose which characterized the fulminant cases.
The typical rusty sputum was rare,
but the presence of some amount of blood was the rule.
From the beginning the physical signs were confusing. Typical signs of consolidation were seldom found, and then late.
After some experience with these cases most observers concluded that
the diagnosis of pulmonary involvement was better made from the general course and symptomatology than from physical signs. Here, too, the X-ray examination proved very valuable, as was stated above. The early signs of pneumonia were confined to the presence of fine scattered râles, and as these râles were found in many apparently uncomplicated influenza cases their significance was not clear. As the involvement proceeded, dullness became evident on percussion, and breath sounds, voice, and fremitus were diminished, thus suggesting fluid in the pleura. Areas of tympany were also observed. After several days the confluence, or extension of consolidated areas, often produced typical signs of consolidation.
Pleuritic friction was often heard.
The heart action was slow in proportion to the temperature, and right-sided dilatation was not the rule even in severe and fatal cases. Low blood pressure was noted, in some cases the systolic blood pressure falling as low as 80 mm. without a necessarily fatal issue.
<hr size="1" noshade="noshade">
The temperature was very variable, usually of a fairly continous type, but in some cases remissions with sweating were frequent even without suppurative complications. The leucocyte counts were also variable, some fatal cases showing no change from the initial leucopenia. In others a marked polynucleosis supervened. Pneumococcus cases showed this rise earlier than did cases infected with streptococci. Blood cultures were positive in a relatively small proportion of cases, and pneumococcus infection gave the great majority of the positive results.
Toxic nephritis, varying in degree, occurred in nearly every case.
...
