Bacteriology, which first took away the idea of diathesis, is now giving it back. The discovery of the tubercle bacillus as the cause of tuberculosis banished the tubercular diathesis apparently forever; but, step by step, through bacteria and then toxins and antitoxins and now through anaphylaxis and allergie, bacteriology is bringing back the old conception of an inherited or acquired susceptibility to attack. Call the old tubercular diathesis a sensitization and you have made it the most modern of modern discoveries. So, also, step by step, through bacteriology with its toxins and antitoxins and now with anaphylaxis, from the philosophic ash-heap on which we thought to have thrown it for good and all, like an old family cat that we thought was dead, comes creeping back that old conception of a gouty diathesis or arthritism, not as dead as we thought it, to complete the explanation of the existence of hay fever.
I am far from saying that calling hay fever a form of gout ends the subject. I say only that bringing such a common and puzzling disorder as hay fever in line with such a common and puzzling disorder as gout brings us a long step nearer to solving the puzzle that lies behind both of them; and I say also that, in the records of this work, the name of Gueneau de Mussy, who first recognized this relation clinically, deserves a place.
Gout as an anaphylaxis, hay fever as an external expression of gout, what a vista of therapeutic possibilities is opened up by these simple experiments with pollen extracts and foods. The subject ramifies in every direction, touching the gouty form of Bright's disease, gouty heart disease, endocarditis and pericarditis, the popular "hardening of the arteries," which may prove after all not to be due to meat in all cases or alcohol in all cases but certain foods in certain cases, the increase in deaths from heart disease and kidney disease in the fifth decade of life. The correlation of these gouty problems with this work in the prevention and cure of hay fever anaphylaxis awaits a Lister or a Pasteur or a Koch who will have an eye to see and a patient industry to search and find.
When you have established hay fever as anaphylaxis or lowered resistance to a specific proteid, you may be sure that the immunologist will seize the patient as his own, carry him off to the laboratory, and there attempt to raise his resistance or develop immunity to the attacking proteid by giving minute doses of the poison gradually increased. The success of this procedure will be related in the next chapter.
CHAPTER XI
IMMUNIZING WITH POLLEN EXTRACT
The idea of preventing disease and poisoning by preparing the body with minute doses of that poison, gradually increasing until the body is immune, is an ancient one. The practice is Ur-alt, as my favorite German history books say; for it has been found among savages and primitive peoples and is practised in a crude way by every boy who accustoms himself to that noxious weed, tobacco. Then, there are the Psylli, whom Lucan tells of, who were by heredity immune to snake poison and who could make the favored stranger immune by inoculating him with small doses (Pharsalia, Book ix); and old King Mithridates, of Pontus, who believed in preparedness and kept himself prepared for the attentions of his faithful subjects by taking small doses of poison every day, keeping himself immune should by any accident some poison slip into his porridge (Pliny, Book xxv). Old King Mithridates was a good immunologist. He knew the transient nature of immunity and kept the treatment up. He knew that, if he stopped taking the poison for a week or so, he would go into a state of anaphylaxis and the next dose would kill him; so he kept himself in a state of anti-anaphylaxis by not permitting too long a time to elapse between doses, after the most approved rules of modern immunology. That patient whom Goodale immunized against horse-asthma who objected to a treatment that had to be taken for the rest of her life, should learn of old King Mithridates the true practice of immunity.
This is still the weak point of artificial immunity; it does not last very long. You can immunize a guinea-pig or a patient to almost anything now-a-days by giving him minute doses gradually increased but the immunity passes off quite rapidly when the treatment is stopped. We have still something to learn from Nature in this respect. Nature can give us one dose of yellow-fever or scarlet-fever or small-pox or measles and make us immune for life but your artificially produced immunity may last for a few weeks or months only. Our closest imitation of natural immunity is vaccination against small-pox. Here we produce an actual disease, cow-pox; yet, even here, we are not at all sure how long immunity lasts. Even in Jenner's time, the original belief in protection for life came down to seven years and our modern health boards would vaccinate every two years or, in the presence of an epidemic, more frequently.
However, Nature is a wasteful worker, wasteful of her material, and she kills a great many of her children with measles and scarlet-fever and small-pox and yellow-fever while immunizing the lucky ones. A Health Board that would kill so many people while immunizing the rest would be a public scandal. Yet it is probable that Nature's way is the most effective and that the best immunizer is the disease itself, as Koch found with tuberculosis among his guinea-pigs that the best protection against tuberculosis was inoculation with living tubercle bacilli, not with dead ones; and the autopsies show that the majority of the human race that grow up at all have been successfully immunized against tuberculosis by a mild local attack of the disease.