The high incidence of pneumonia among measles patients coming into the hospital prior to, with, or immediately following the height of the influenza epidemic is very striking. It so happens that half of the total number of measles cases considered, date their onsets prior to October 15. From the 433 cases included in this first half, 42 cases of pneumonia arose, while from the 434 cases arising during the two months following October 15, only 14 or one-third as many cases of pneumonia developed. These figures very strongly suggest that influenza played a large part in the production of the pneumonia with measles in this group of cases.
Again the 9.7 per cent incidence of pneumonia in the first half of cases considered, approaches the 12 per cent incidence of pneumonia following influenza observed in the epidemic at Camp Pike, while the incidence of 3.2 per cent in the second half of the cases conforms more nearly to figures for pneumonia following measles in the army prior to the pandemic of influenza.
It has been shown that the prevalence of B. influenzæ at Camp Pike increased with the passing of the wave of influenza (p. [40]) and that this increase applied to the measles admissions. For a time the separation of measles patients carrying B. influenzæ as identified by throat culture on admission, from those free from it, was practiced. All cases were then followed up by weekly throat cultures, and cases in negative wards on being identified as positives were transferred.
This practice was discontinued as impractical when it became apparent that about 80 per cent of patients with measles would be found positive for B. influenzæ when repeated throat cultures were made during their hospital treatment. The dissemination of B. influenzæ through the wards from which we were attempting to exclude it took place much faster than we could follow its spread by cultural methods. When this became evident, the practice of separating the two groups of patients with reference to B. influenzæ was discontinued and the great inconvenience of repeated transfer of patients was largely eliminated.
Table LX gives the findings in 426 cases of measles cultured for B. influenzæ during the period when the practice of separating measles patients carrying B. influenzæ from those not carrying the organisms was followed.
| Table LX | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Results of Repeated Throat Cultures for B. Influenzæ on 426 Cases of Measles, Camp Pike, Sept. 15 to Oct. 20, 1918. | |||||||||||
| GROUPS | TOTAL NUMBER CULTURED IN GROUP | GROUP NO. NEGATIVE FOR B. INFLUENZÆ ON ADMISSION | RESULTS OF CULTURES TO DATE | GROUP NO. POSITIVE FOR B. INF. TO DATE | GROUP OF POSITIVES DEVELOPING TO DATE IN CASES NEGATIVE FOR B. INF. ON ADMISSION | PER CENT OF GROUP POSITIVE FOR B. INF. TO DATE | GROUP PER CENT OF POSITIVES TO DATE AMONG CASES NEGATIVE FOR B. INF. ON ADMISSION | ||||
| 1ST CULTURE | 2ND CULTURE | 3RD CULTURE | 4TH CULTURE | NO. IN EACH CLASS | |||||||
| I | |||||||||||
| 1st culture on admission | 426 | − | 274 | 152 | 35.6 | ||||||
| + | 152 | ||||||||||
| II | |||||||||||
| 1st and 2nd culture, after one week in hospital | 201 | 143 | − | − | 75 | 126 | 68 | 62.7 | 47.5 | ||
| − | + | 68 | |||||||||
| + | + | 29 | |||||||||
| + | − | 29 | |||||||||
| III | |||||||||||
| 1st, 2nd and 3rd cultures after two weeks in hospital | 94 | 69 | − | − | − | 22 | 72 | 47 | 77.7 | 68.1 | |
| − | − | + | 18 | ||||||||
| − | + | − | 13 | ||||||||
| − | + | + | 16 | ||||||||
| + | + | + | 8 | ||||||||
| + | − | + | 6 | ||||||||
| + | + | − | 4 | ||||||||
| + | − | − | 7 | ||||||||
| IV | |||||||||||
| 1st, 2nd, 3rd and 4th cultures after three weeks in hospital | 25 | 19 | − | − | − | − | 4 | 21 | 15 | 84 | 79. |
| − | − | − | + | 3 | |||||||
| − | − | + | + | 3 | |||||||
| − | − | + | − | 2 | |||||||
| − | + | + | + | 2 | |||||||
| − | + | − | + | 2 | |||||||
| − | + | + | − | 2 | |||||||
| − | + | − | − | 1 | |||||||
| + | + | + | + | 2 | |||||||
| + | − | − | + | 1 | |||||||
| + | − | + | + | 1 | |||||||
| + | + | + | − | 1 | |||||||
| + | − | − | − | 1 | |||||||
On admission 35.6 per cent of the patients were found positive for B. influenzæ. Repeated throat cultures were not confined to those appearing negative on this initial culture, but were made on all patients without regard to their being previously positive or negative. By a summation of the results of the weekly cultures of all patients, the percentage of patients carrying B. influenzæ rises from 35.6 per cent on admission, to 62.7 per cent after one week; to 77.7 per cent after two weeks; to 84 per cent after three weeks in the hospital.
To gain some idea of the rate of spread of B. influenzæ in wards receiving only patients whose throat cultures were negative for B. influenzæ on admission, a similar summation of the results of repeated throat cultures on patients in negative wards shows weekly increases from 47.5 per cent after one week, to 68.1 per cent after two weeks; to 79 per cent at the end of three weeks.
These results demonstrate quite clearly that the measles wards were saturated with B. influenzæ during the period of the influenza epidemic. Conditions within the measles wards with regard to B. influenzæ were not at all different from those in the camp community during this period. While no clinical methods could be relied upon to diagnose influenza in the presence of an acute attack of measles, there is every reason to believe that the occurrence of clinical influenza with measles was no less frequent than was its incidence in the camp at large, that is, about 20 to 25 per cent. That influenza played a large part in determining predisposition to the complications of measles in this series seems evident.