The total figures are given in the three charts.
| CHART I. | |||
|---|---|---|---|
| Carnegie Steel Company. | |||
| All Works Except Homestead, City Mills, Columbus, Lucy and Isabella. | |||
| Statistical Report on Inoculation Against Influenza. | |||
| 1. Number of employees who had influenza | 5,728 | 18% | |
| 2. Number of employees who did not have influenza | 24,956 | ||
| Total number of employees | 30,684 | ||
| 3. Total number of persons inoculated | One inoculation | 2,983 | |
| Two inoculations | 3,675 | ||
| Three inoculations | 4,626 | ||
| Four inoculations | 10,053 | ||
| Total | 21,337 | ||
| 4. Cases influenza developed after | No inoculations | 2,133 | 23% |
| One inoculation | 745 | 25% | |
| Two inoculations | 776 | 21% | |
| Three inoculations | 794 | 17% | |
| Four inoculations | 1,280 | 12% | |
| Total | 5,728 | ||
| 5. Cases influenza pneumonia developed after | No inoculations | 804 | 37% |
| One inoculation | 356 | 48% | |
| Two inoculations | 403 | 52% | |
| Three inoculations | 321 | 40% | |
| Four inoculations | 459 | 36% | |
| Total | 2,343 | ||
| 6. Deaths from influenza and “flu Pneumonia” after | No inoculations | 104 | 4.7% |
| One inoculation | 32 | 4.3% | |
| Two inoculations | 33 | 4.2% | |
| Three inoculations | 21 | 2.6% | |
| Four inoculations | 33 | 2.5% | |
| Total | 223 | 3.9% | |
| CHART II. | |||
| H. C. Frick Coke Company. | |||
| Statistical Report on Inoculation Against Influenza. | |||
| 1. Number of employees who had influenza | 5,248 | 31.4% | |
| 2. Number of employees who did not have influenza | 11,464 | ||
| Total number of employees | 16,712 | ||
| 3. Total number of persons inoculated | No inoculations | 3,122 | |
| One inoculation | 2,483 | ||
| Two inoculations | 2,548 | ||
| Three inoculations | 3,550 | ||
| Four inoculations | 5,009 | ||
| Total | 13,590 | ||
| 4. Cases influenza developed after | No inoculations | 1,495 | 47.9% of (3 |
| One inoculation | 634 | 25.5% | |
| Two inoculations | 770 | 30.2% | |
| Three inoculations | 1,078 | 30.4% | |
| Four inoculations | 1,271 | 25.0% | |
| Total | 5,248 | ||
| 5. Cases influenza pneumonia developed after | No inoculations | 94 | 6.3% of (4 |
| One inoculation | 33 | 5.2% | |
| Two inoculations | 42 | 5.4% | |
| Three inoculations | 69 | 6.4% | |
| Four inoculations | 85 | 6.7% | |
| Total | 323 | 6.1% of (4 total | |
| 6. Deaths from influenza and “flu | No inoculations | 30 | 2.0% of (4 |
| One inoculation | 13 | 2.0% | |
| Two inoculations | 21 | 2.9% | |
| Three inoculations | 16 | 1.5% | |
| Four inoculations | 37 | 2.9% | |
| Total | 117 | 2.2% of (4 | |
| CHART III. | |||
| Bessemer & Lake Erie Railroad. | |||
| Statistical Report on Inoculation Against Influenza. | |||
| 1. Number of employees who had influenza | 1,275 | 24% | |
| 2. Number of employees who did not have influenza | 3,986 | ||
| Total number of employees | 5,261 | ||
| 3. Total number of persons inoculated | No inoculations | 3,091 | |
| One inoculation | 232 | ||
| Two inoculations | 249 | ||
| Three inoculations | 479 | ||
| Four inoculations | 1,210 | ||
| Total | 2,170 | ||
| 4. Cases influenza developed after | No inoculations | 705 | 55% |
| One inoculation | 111 | 48% | |
| Two inoculations | 91 | 36% | |
| Three inoculations | 129 | 27% | |
| Four inoculations | 239 | 19% | |
| Total | 1,275 | ||
| 5. Cases influenza pneumonia developed after | No inoculations | 283 | 40% of (4 |
| One inoculation | 75 | 67% | |
| Two inoculations | 59 | 64% | |
| Three inoculations | 51 | 42% | |
| Four inoculations | 69 | 28% | |
| Total | 537 | ||
| 6. Deaths from influenza and “flu Pneumonia” after | No inoculations | 40 | 5.6% of (4 |
| One inoculation | 5 | 4.5% | |
| Two inoculations | 0 | ||
| Three inoculations | 0 | ||
| Four inoculations | 3 | 4.3% | |
| Total | 48 | ||
Charts I and III show a decrease in the incidence of influenza in direct proportion to the number of inoculations given. This finding would have been very important had vaccination been completed before the epidemic appeared. There is, however, no convincing evidence in either of these charts that the vaccine cut down the relative number of pneumonias, or decreased the death rate to any appreciable extent. Chart I also shows the interesting fact that influenza occurred slightly more often among those who had one inoculation than among those who were not vaccinated at all.
Chart II would indicate that influenza occurred much less frequently in the vaccinated than in the control group, but a closer analysis brings out the contradictory finding that influenza occurred at the same rate in the group of 634 persons who had only 1 dose that it did in the group of 1,271 who completed the course.
The reports from the separate communities were so conflicting that to attempt to analyze them leads only to confusion.
No reports of harmful effects from the use of the vaccine were received, and several physicians who attended sick employees say that, even though the figures do not show it, they feel certain that the vaccinated persons in general were not as sick as those who were not vaccinated.
On account of the conditions under which the vaccinations were done and the reports compiled, Dr. Sherman has not felt justified in making a report, fearing that erroneous conclusions might be drawn from the data. We are greatly indebted to him for the use of his reports, without which our account of the influenza epidemic in Pittsburgh would have been very incomplete.
2. Another large steel corporation who used vaccine but asked that their names be withheld furnished the following report. During the epidemic the company offered free vaccination to its 27,000 employees and their families. Commercial mixed vaccines were used, three injections given, and vaccination begun on October 19, which was about the time of the peak of the epidemic in Pittsburgh. The results include a record of all employees who lost over six days between October 1 and November 30.
| EMPLOYEES | Morbidity | Pneumonia | Mortality | ||||
|---|---|---|---|---|---|---|---|
| No. | % | No. | % | No. | % | ||
| Received only one dose | 3,895 | 511 | 13.13 | 31 | 0.8 | 28 | 0.72 |
| Received only two doses | 3,329 | 414 | 12.44 | 40 | 1.2 | 19 | 0.57 |
| Received all three doses | 9,897 | 468 | 4.75 | 46 | 0.46 | 32 | 0.32 |
| Total of above | 17,119 | 1393 | 8.14 | 117 | 0.68 | 79 | 0.46 |
| Received no doses | 10,036 | 1522 | 15.17 | 154 | 1.53 | 106 | 1.06 |
| Total for both groups | 27,155 | 2915 | 11.66 | 271 | 1.10 | 185 | 0.76 |
Before satisfactory conclusions can be drawn from these figures it is necessary to know how many of the 10,036 persons became sick before vaccination, and whether or not the rate of decrease in this group was not similar to that shown by the number of patients who developed influenza during the intervals between their doses of vaccine. The relatively high percentage of cases following the first and second doses are capable of explanation on one, or perhaps on all, of the three following grounds: (a) the general subsidence of the epidemic, which showed a rapid decrease by the time the third dose was given; (b) the increased protection afforded by the three doses of vaccine, and (c) the broken resistance of the patient following sudden sensitization by the vaccine.