D

ISCUSSING "Prevention of Pneumonia" in a recent article*, Dr. Rufus Cole of the Rockefeller Institute emphasizes the new knowledge of the subject which has been gained from investigations brought about by the serious epidemic of pneumonia in the army camps last winter. He points out that an article on this subject a year ago would have dealt with the prevention of acute lobar pneumonia only, but that more recent experience demonstrates the need for considering broncho or lobular pneumonia also.

Lack of general recognition of the fact that these two distinct diseases existed side by side in the camps, and inability to differentiate between the two diseases even where their separate existence was recognized makes it impossible for us to know the relative incidence of the two kinds of pneumonia last year. The hope is expressed, however, that with the better laboratory facilities and the more widespread knowledge of the methods of differential diagnosis which now prevail, more accurate differentiation will henceforth be made.

Lobar and broncho pneumonia are considered independently, as they require different preventive methods.

Lobar pneumonia is caused by the pneumococcus, which organism is widely distributed in the mouths of healthy individuals and survives for considerable periods in dust. Preventive methods to be followed

depend upon the answer to the question: Do persons acquire the disease because they receive these bacteria into their mouths or upon their respiratory mucous surfaces, or do they acquire it because of some earlier factor which has increased their susceptibility to the disease? If the former is the reason, then measures for preventing the distribution of the bacteria must be employed; if the latter, then the distribution of the bacteria is of slight importance and attention must be given to the factors influencing resistance.

The resistance factor was considered the important one so long as all pneumococci were considered identical, but recent demonstration of the existence of several types of pneumococci and of the fact that the types causing two-thirds of the cases are not found in the mouths of well persons, other than carriers who have been in close association with patients, justifies measures to restrict the distribution of these types of pneumococci. The experience of physicians who have observed many pneumonia cases bears out this justification, as all have seen examples of contact infection, and recent studies have demonstrated the not infrequent association of cases due to pneumococci of the same type. Similar preventive measures in the case of pneumonia of the less virulent types are made advisable by the long recognized fact that the virulence of any bacterium for a given

species of animal is increased by repeatedly passing the bacterium through animals of that species.

Experience indicates that the factor of lowered resistance plays a certain part in pneumonia infection, so measures to prevent undue exposure and lowered resistance are recommended for preventive purposes, together with isolation of patients to as great an extent as possible. Experiments with vaccination against Types I, II and III last winter produced results which, while not conclusive, are sufficiently promising to justify more extended tests during the coming winter. In 12,000 men inoculated at Camp Upton last winter not one case of pneumonia due to pneumococci of Types I, II or III occurred, III occurred, although there was a considerable number of such cases among uninoculated men in the same camp.

Broncho pneumonia, which received serious attention for the first time last winter, is believed to have been due, so far as the cases in the camps are concerned, to one organism, a hemolytic streptococcus. Whether all strains of this organism which have been isolated are identical has not been discovered. If they are found identical, the problem of prevention will be comparatively simple. If they are not identical, the conclusion must be that the essential factor causing the epidemic was something other than the organism, and the study of the spread of the disease will be made more difficult. If it should be found that these streptococci are identical with streptococci which exist as harmless organisms widely distributed outside the human body and in the throats of healthy persons, then the difficulties will be still greater. Present knowledge indicates, how

ever, that hemolytic streptococci are rare in normal throats, except in the presence of streptococcus sore throat, and that such organisms found in dairy products are of a bovine type, harmless to man. At present, therefore, we seem justified justified in considering persons who harbor large numbers of actively hemolytic streptococci in the throat as potential carriers, and in giving some attention to the possibility of infection through dust, dried sputum, etc., and through food. The disease is spread, it appears at present, by fairly direct transfer of the infectious agent from the patient or a healthy carrier, either by droplet infection or through dust. The pathology of the disease suggests a relatively high immunity in man, despite the high fatality, and therefore a relatively large number of healthy carriers.

The recent epidemic among the soldiers started with infection of patients suffering from, or convalescent from, measles, none of the earlier attacks being upon healthy individuals. Later such primary infections appeared, however, affording some basis for the theory. that the streptococci, first attacking persons whose resistance had been weakened by measles infection, were by that fact rendered more virulent and enabled to attack persons suffering from other respiratory diseases, such as lobar pneumonia, and finally acquired such. virulence that they may now infect healthy persons.

Measures probably advisable to prevent and restrict broncho pneumonia are:

(1) Precautions to prevent the infection of persons highly susceptible to the disease, especially patients with measles, lobar pneu

monia and other respiratory infections;

(2) Prompt diagnosis and as rigid isolation as possible in al cases of the disease;

(3) Preventive inoculation impossible until methods have been discovered with further investigation;

(4) Detection and isolation of the healthy carrier-impracticable

at present, but similar results can be obtained by avoiding crowding and by educating men to use more care in disposing of their oral and nasal secretions.

Knowledge by the surgeons of the early symptoms of the disease, well equipped diagnostic laboratories and properly organized infectious disease hospitals are essential to the effective carrying out of these measures in the army.

FEDERAL FUNDS MAY

AID STATES' CHILD

HYGIENE ACTIVITIES Federal financial aid for child hygiene activities of the states will be provided, if Congress passes duplicate bills introduced by Representative Jeanette Rankin of Montana, and Senator Robinson of Arkansas with the aproval of the Children's Bureau of the Department of Labor.

The bill would grant Federal aid to state work for mothers and babies in rural districts, provided this work meets the general requirements of the bill and such detailed standards as may be fixed by the Children's Bureau.

The amount allowed for the first year would be $1,480,000, including the expenses of Federal administration. This amount would be increased each year, until in 1923-24 it would be $2,480,000. Each state would, under certain conditions, receive $10,000 annually. The remainder would be divided among the states upon the basis of their rural population, but amounts beyond the first $10,000 would be available only after a state had appropriated an equal sum.

A subsidy of this kind is provided by the British government for local child welfare work. The British, however, are appropriating a larger sum, in proportion to infant population, than is proposed for the United States. The British subsidy amounts to approximately $1,100,000 per year for fewer than 709,000 babies under one year of age, while the amount proposed for this country is $1,480,000 for more than 1,500,000 babies in the rural districts.

T. B. CASE ESTIMATE

MAY BE TOO SMALL Statistics compiled as the result of community-wide medical examinations in connection with the health demonstration at Framingham, Mass., show that tuberculosis exists there in the ratio of twentyone case to every death, if arrested cases are included, or nine cases to one death if only active cases are considered. The generally accepted estimate of this ratio. in the past has been five or six cases to one death.