Isolation of each patient with pneumonia is the most effective way of protecting him from infection and of preventing him from becoming a possible source of danger to others. The effectiveness of this isolation will depend upon the separation of patients by some means more effective than the cubicles composed of sheets heretofore employed, upon an aseptic technic sufficiently rigid to prevent the transfer of pyogenic infection to pneumonia patients, and upon the exclusion from the ward of those who harbor S. hemolyticus.
Even should each patient be completely isolated from his neighbors, no effort should be neglected to determine, as far as possible, the nature of the infection with which he suffers. In the presence of an overwhelming epidemic such as that which attacked our army camps, the bacteriologic work which is required may be far beyond the facilities which are available and in many instances it may be wholly impossible. Nevertheless effective control of streptococcus pneumonia will depend upon its recognition as soon as it appears, and bacteriologic examination of the sputum offers the readiest means for its identification. The routine performance of autopsies will furnish an index of the success of the measures in force, and the discovery of suppurative pneumonia will suggest the presence of imminent danger.
However perfect the organization of pneumonia wards and however accurate the aseptic technic in force, it is desirable to separate as far as possible those infected with streptococcus from those who are free from this infection, so that the accuracy of the technic in force may not be put to too severe a test. When streptococcus pneumonia has appeared in a ward it should be closed to further admissions.
Those who are concerned in the planning and construction of military and other similar hospitals might well give special attention to the possibility of epidemics such as those which we have experienced, and special provision might be made to avoid overcrowding in the presence of a demand far in excess of the routine need for hospital facilities. In the construction of these hospitals appropriate provision should be made for the care of patients with pneumonia. Medical officers should receive detailed instruction in the organization and conduct of wards designed for the treatment of pneumonia.
APPENDIX
EXPERIMENTAL INOCULATION OF MONKEYS WITH BACILLUS INFLUENZÆ AND MICROORGANISMS ISOLATED FROM THE PNEUMONIAS OF INFLUENZA
Eugene L. Opie, M.D.; Allen W. Freeman, M.D.; Francis G. Blake, M.D.; James C. Small, M.D.; and Thomas M. Rivers, M.D.
Experiments were undertaken at Camp Pike in December, 1918, to determine whether bacteria freshly isolated from patients suffering with influenza and pneumonia during the outbreak of influenza and its associated pneumonias were capable of producing similar diseases when introduced into the respiratory passages of monkeys. The number of animals available for the study was limited. The attempt was made (a) to determine if B. influenzæ produces in monkeys a disease comparable to influenza of human beings, and (b) to determine so far as possible, with the limited opportunity, the character of the lesions produced by combinations of pneumococcus or S. hemolyticus with B. influenzæ and to compare these lesions with lesions produced by pneumococcus or by hemolytic streptococcus alone.
Pfeiffer[[107]] found monkeys alone susceptible to invasion by B. influenzæ and obtained no evidence of multiplication of the microorganism within the body of any other animal. A suspension containing mucus from the sputum of a patient with influenza was injected into a monkey. There was elevation of temperature and the animal died after seven days. Lobular patches of atelectasis occurred along the sharp edges of the lungs and the adjacent bronchial branches contained mucus. Cultures on agar from the bronchi remained sterile. Microscopic examination showed the presence of bacilli resembling B. influenzæ. Death was caused, the author states, by an abscess at the site of inoculation and not by the process in the lungs. Three monkeys received each 0.5 c.c. of bouillon containing a blood agar culture injected into the lung through the chest wall. There was elevation of temperature lasting from three to five days with return to normal every morning. There was cough but little evidence of illness. B. influenzæ was introduced by a platinum loop into the nose of a monkey. Febrile reaction is recorded lasting four or five days. Pfeiffer found that guinea pigs and mice were resistant to the microorganism. Large doses injected intravenously caused in rabbits intoxication with dyspnea and evidence of profound muscular weakness.
Kamen[[108]] used a culture of B. influenzæ which was nonpathogenic for mice, but when it was inoculated into the peritoneal cavity with streptococcus both influenza bacilli and streptococci appeared in the blood. Jacobson[[109]] found that B. influenzæ appeared in the blood and viscera of mice killed by intraperitoneal inoculation of B. influenzæ mixed with cultures of streptococcus either living or killed by heat. B. influenzæ which had successively passed through mice, simultaneously inoculated with killed streptococci, acquired such virulence that it was capable of producing septicemia when inoculated alone.
Richie[[110]] introduced by lumbar puncture a suspension of two blood agar cultures of B. influenzæ obtained from the meninges of a patient with influenzal meningitis into the subdural space of a rhesus monkey. Death occurred in eighteen hours and there was beginning meningitis. B. influenzæ was present in the exudate in abundance.