3. Rosenow (21) prepared a mixed vaccine by growing the various bacteria in glucose broth, for from 18 hours to 36 hours, centrifuging and suspending the sediment in salt solution and making up the vaccine on a percentage basis.
FORMULA OF VACCINE
| Pneumococci, Types I (10 per cent.), II (14 per cent.) and III (6 per cent.) | 30 per cent. |
| Pneumococci Group IV and the allied green-producingdiplostreptococci described | 30 per cent. |
| Hemolytic Streptococci | 20 per cent. |
| Staphylococcus Aureus | 10 per cent. |
| Influenza bacillus | 10 per cent. |
Most of the vaccine was distributed within a radius of 200 miles of Rochester, Minn., but samples were furnished to physicians all over the country, who agreed to return statistics on its use. No evidence was found that this vaccine caused a temporary break in the resistance of the user. Out of a total of 20,972 persons vaccinated, 14.6 cases of influenza, 1.8 cases of pneumonia, with 1.8 mortality, occurred per thousand in the six weeks following vaccination. As controls, he took “such persons in institutions, colleges, factories and communities where vaccine was used, and included only those reports which contained accurate data as to the incidence and mortality among them.” Among 61,753 such controls he found 229 cases of influenza, 15.7 cases of pneumonia and 3.4 deaths per thousand. He concluded from his results that “it appears possible to afford a definite degree of immunity by prophylactic inoculations to persons against the more serious respiratory infections during the present epidemic.” It is quite difficult to agree with Rosenow in his interpretation of the figures as presented by him, inasmuch as he made no allowance for the stage of the epidemic at which vaccination was carried out, either among the vaccinated or the non-vaccinated. Such a comparison would be well nigh impossible where the vaccine was sent in varying quantities to such a large number of places.
4. League Island Report (22). Vaccines were used as a preventive in 50 persons, most of whom were hospital apprentices and in the wards 12 to 15 hours a day. Other precautions were used, such as masks, but not a single case developed in the group. The vaccine was used as a curative agent in 50 uncomplicated cases; none of the patients injected early developed pneumonia.
5. Puget Sound Navy Yards Report (23). The vaccine used at this station was made from hæmolytic streptococci, no other organisms being used; 4,212 men were vaccinated, and not one died from influenza. Among 111 Philippinos isolated and vaccinated there occurred only 2 cases. Among 361 marines vaccinated early there occurred 2 cases. Among 62 marines at the ammunition depot who were vaccinated early there occurred 3 cases, only 1 of which occurred after completion of vaccination. Among 662 bluejackets at Seattle Training Camp only 10 men developed the disease. Among 83 at the aviation corps there were 32 cases—31 of them developed the disease within a few hours after the first injection. There were no deaths in any of the above groups. The period of observation was closed on October 21, and so few cases of influenza appeared subsequent to that date that it seemed that the epidemic was practically over at the time the data was obtained.
6. Kitano (24) used a vaccine for prophylaxis containing 0.2 m.g. of Pfeiffer bacilli per c.c. on 10,300 persons with encouraging results. He used vaccine for treatment on 87 patients, without any deaths. In the same group were 270 cases treated in the usual way, with 23 per cent. mortality. The vaccine lessened the severity, shortened the period of illness, and lowered the mortality.
7. Wynn (25) used mixed vaccines in the treatment of influenza, and believed they aborted the disease if given early.
8. Norman White (26) states that vaccination in India would be impractical, because the disease is so brief and severe that it would be over before innumerable doctors could complete inoculations.
9. Whitingham and Sims (27) reported the use of a mixed vaccine in an institution where 156 were inoculated and 149 were not. The case incidence was 5 per cent. among the vaccinated and 12 per cent. among the controls. No statement of the stage of the epidemic at which vaccination was done is mentioned in the report.