16 FEBRUARY 1940, Page 20

THE CAUSE OF INFLUENZA Snt,—May I point out that your

medical correspondent's statements as to the cause of influenza and other " virus " diseases such as small-pox, measles, rabies, foot-and-mouth disease are incomplete? It is quite true that some of the viruses are so minute—such as that of foot-and-mouth disease —that it has been seriously debated whether they could be alive. That they are living is demonstrated by the fact, proved in every case, that a bacillus can be precisely and in- evitably grown from the virus if proper cultural methods are used. This is of the first practical importance since a killed antigen (vaccine) of the bacillary phase gives us a powerful, safe and precise method of prevention and cure, while a killed antigen of the virus phase is relatively impotent.

In true influenza, such as the pandemic of 1918 and subse- quent epidemics, the influenza bacillus of Pfeiffer was present in every case in the respiratory passages. In the tissues, such as the brain, it was in its virus phase, where it pro- duced encephalitis lethargica—" Sleepy Sickness "—which was quickly and precisely cured by an antigen of the bacillary phase from the throat. The exact microbal cause of every case of so-called influenza can be discovered by proper cul- ture and a specific remedy produced in twelve hours at the most, so that a fatal issue is a very rare event.

Experimentally and clinically this point of view has been proved beyond yea or nay, but is still officially ignored. It is quite a simple experiment to filter the blood of a guinea- pig artificially infected with foot-and-mouth disease and re- cover the bacillus from the filtered material and to give another guinea-pig foot-and-mouth disease by injecting the bacillus. A killed antigen of the bacillus easily protects a guinea-pig from the disease, whether infected in the bacillary or virus phases, and this simple prevention has been found effective in cattle exposed to dire infection. An antigen of the influenza bacillus is equally effective for both prevention and cure if properly grown and manufactured.—Truly yours,