The simplest and most direct definition of syphilis is that it is a contagious constitutional disease, due to a germ, running a prolonged course, and at one time or another in that course is capable of affecting nearly every part of the body. One of the most important parts of this rather abstract statement is that which relates to the germ. To be able to put one's finger so definitely on the cause of syphilis is an advantage which cannot be overestimated. More than in almost any other disease the identification of syphilis at its very outset depends upon the seeing of the germ that causes it in the discharge from the sore or pimple which is the first evidence of syphilis on the body. On our ability to recognize the disease as syphilis in the first few days of its course depends the greatest hope of cure. On the recognition of the germ in the tissues and fluids of the body has depended our knowledge of the real extent and ravages of the disease. With the knowledge that the germ was related to certain other more familiar forms, Ehrlich set the trap for it that culminated in salvarsan, or "606," the powerful drug used in the modern treatment. By the finding of this same germ in the nervous system in locomotor ataxia and general paralysis of the insane, the last lingering doubt of their syphilitic character was dispelled. Every day and hour the man who deals with syphilis in accordance with the best modern practice brings to bear knowledge that arises from our knowledge of the germ cause of syphilis. No single fact except perhaps the knowledge that certain animals (monkeys and rabbits especially) could be infected with it has been of such immense practical utility in developing our power to deal with it.

The germ of syphilis,[3] discovered by Schaudinn and Hoffmann in 1905, is an extremely minute spiral or corkscrew-shaped filament, visible under only the highest powers of the microscope, which increase the area of the object looked at hundreds of thousands of times, and sometimes more than a million of times. Even under such intense magnifications, it can be seen only with great difficulty, since it is colorless in life, and it is hard to color or stain it with dyes. Its spiral form and faint staining have led to its being called the SpirochÆta pallida.[4] It is best seen by the use of a special device, called a dark-field illuminator, which shows the germ, like a floating particle in a sunbeam, as a brilliant white spiral against a black background, floating and moving in the secretions taken from the sore in which it is found. Some means of showing the germ should be in the hands of every physician, hospital, or dispensary which makes a claim to recognize and treat syphilis.

Syphilis a Concealed Disease.—Syphilis is not a grossly conspicuous figure in our every-day life, as leprosy was in the life of the Middle Ages, for example. To the casually minded, therefore, it is not at all unreasonable to ask why there should be so much agitation about it when so little of it is in evidence. It takes a good deal out of the graphic quality of the thing to say that most syphilis is concealed, that most syphilitics, during a long period of their disease, are socially presentable. Of course, when we hear that they may serve lunch to us, collect our carfare, manicure our nails, dance with us most enchantingly, or eat at our tables, it seems a little more real, but still a little too much to believe. Conviction seems to require that we see the damaged goods, the scars, the sores, the eaten bones, the hobbling cripples, the maimed, the halt, and the blind. There is no accurate estimate of its prevalence based on a census, because, as will appear later, even an actual impulse to self-betrayal would not disclose 30 to 40 per cent of the victims of the disease. Approximately this percentage would either have forgotten the trivial beginnings of it, or with the germs of it still in their brains or the walls of their arteries or other out-of-the-way corners of their bodies, would think themselves free of the disease—long since "cured" and out of danger.

How Much Syphilis is There?—Our entire lack of a tangible idea of how much syphilis there really is among us is, of course, due to the absence of any form of registration or reporting of the disease to authorities such as health officers, whose duty it is to collect such statistics, and forms the principal argument in favor of dealing with syphilis legally as a contagious disease. Such conceptions of its prevalence as we have are based on individual opinions and data collected by men of large experience.

Earlier Estimates of the Prevalence of Syphilis.—It is generally conceded that there is more syphilis among men than women, although it should not be forgotten that low figures in women may be due to some extent to the milder and less outspoken course of the disease in them. Five times more syphilis in men than women conservatively summarizes our present conceptions. The importance of distinguishing between syphilis among the sick and among the well is often overlooked. For example, Landouzy, in the LaËnnec clinic in Paris, estimated recently that in the patients of this clinic, which deals with general medicine, 15 to 18 per cent of the women and 21 to 28 per cent of the men had syphilis. It is fair to presume, then, that such a percentage would be rather high for the general run of every-day people. This accords with the estimates, based on large experience, of such men as Lenoir and Fournier, that 13 to 15 per cent of all adult males in Paris have syphilis. Erb estimated 12 per cent for Berlin, and other estimates give 12 per cent for London. Collie's survey of British working men gives 9.2 per cent in those who, in spite of having passed a general health examination, showed the disease by a blood test. A large body of figures, covering thirty years, and dating back beyond the time when the most sensitive tests of the disease came into use, gives about 8 per cent of more than a million patients in the United States Public Health and Marine Hospital Service as having syphilis. It should be recalled that this includes essentially active rather than quiescent cases, and is therefore probably too low.

Current Estimates of the Prevalence of Syphilis.—The constant upward tendency of recent estimates of the amount of syphilis in the general population, as a result of the application of tests which will detect even concealed or quiescent cases, is a matter for grave thought. The opinion of such an authority as Blaschko, while apparently extreme, cannot be too lightly dismissed, when he rates the percentage of syphilitics in clerks and merchants in Berlin between the ages of 18 and 28 as 45 per cent. Pinkus estimated that one man in five in Germany has had syphilis. Recently published data by Vedder, covering the condition of recruits drawn to the army from country and city populations, estimate 20 per cent syphilitics among young men who apply for enlistment, and 5 per cent among the type of young men who enter West Point and our colleges. It can be pointed out also with justice that the percentage of syphilis in any class grouped by age increases with the age, since so few of the cases are cured, and the number is simply added to up to a certain point as time elapses. Even the army, which represents in many ways a filtered group of men, passing a rigorous examination, and protected by an elaborate system of preventions which probably keeps the infection rate below that of the civil population, is conceded by careful observers (Nichols and others) to show from 5 to 7 per cent syphilitics. Attention should be called to the difference between the percentage of syphilis in a population and the percentage of venereal disease. The inclusion of gonorrhea with syphilis increases the percentages enormously, since it is not infrequently estimated that as high as 70 per cent of adult males have gonorrhea at least once in a lifetime.

On the whole, then, it is conservative to estimate that one man in ten has syphilis. Taking men and women together on the basis of one of the latter to five of the former, and excluding those under fifteen years of age from consideration, this country, with a population of 91,972,266,[5] should be able to muster a very considerable army of 3,842,526, whose influence can give a little appreciated but very undesirable degree of hyphenation to our American public health. In taking stock of ourselves for the future, and in all movements for national solidarity, efficiency, and defense, we must reckon this force of syphilo-Americans among our debits.

The Primary Stage of Syphilis

The So-called Stages of Syphilis.—The division of the course of syphilis into definite stages is an older and more arbitrary conception than the one now developing, and was based on outward signs of the disease rather than on a real understanding of what goes on in the body during these periods. The primary stage was supposed to extend from the appearance of the first sore or chancre to the time when an eruption appeared over the whole body. Since the discovery of the SpirochÆta pallida, the germ of the disease, our knowledge of what the germ does in the body, where it goes, and what influence it has upon the infected individual, has rapidly extended. We now appreciate much more fully than formerly that at the very beginning of the disease there is a time when it is almost purely local, confined to the first sore itself, and perhaps to the glands or kernels in its immediate neighborhood. Thorough and prompt treatment with the new and powerful aid of salvarsan ("606") at this stage of the disease can kill all the germs and prevent the disease from getting a foothold in the body which only years of treatment subsequently can break. This is the critical moment of syphilis for the individual and for society, and its importance and the value of treatment at this time cannot be too widely understood.

Peculiarities of the Germ.—Many interesting facts about the SpirochÆta pallida explain peculiarities in the disease of which it is the cause. Many germs can be grown artificially, some in the presence of air, others only when air is removed. The germ of syphilis belongs in the latter class. The germ that causes tuberculosis, a rod-like organism or bacillus, can stand drying without losing its power to produce the disease, and has a very appreciable ability to resist antiseptic agents. If the germ of syphilis were equally hard to kill, syphilis would be an almost universal disease. Fortunately it dies at once on drying, and is easily destroyed by the weaker antiseptics provided it has not gained a foothold on favorable ground. Its inability to live long in the presence of air confines the source of infection largely to those parts of the body which are moist and protected, and especially to secretions and discharges which contain it. Its contagiousness is, therefore, more readily controlled than that of tuberculosis. It is impossible for a syphilitic to leave a room or a house infected for the next occupants, and it is not necessary to do more than disinfect objects that come in contact with open lesions or their secretions, to prevent its spread by indirect means. Such details will be considered more fully under the transmission and hygiene of the disease.

Mode of Entry of the Germ.—The germ of the disease probably gains entrance to the body through a break or abrasion in the skin or the moist red mucous surfaces of the body, such as those which line the mouth and the genital tract. The break in the surface need not be visible as a chafe or scratch, but may be microscopic in size, so that the first sore seems to develop on what is, to all appearances, healthy surface. It should not be forgotten that this surface need not be confined to the genital organs, since syphilis may and often does begin at any part of the body where the germ finds favorable conditions for growth.

Incubation or Quiescent Period.—Almost all germ diseases have what is called a period of incubation, in which the germ, after it has gained entrance to the body, multiplies with varying rapidity until the conditions are such that the body begins to show signs of the injury which their presence is causing. The germ of syphilis is no exception to this rule. Its entry into the body is followed by a period in which there is no external sign of its presence to warn the infected person of what is coming. This period of quiescence between the moment of infection with syphilis and the appearance of the first signs of the disease in the form of the chancre may vary from a week to six weeks or even two months or more, with an average of about two or three weeks.

In the length of the incubation period and the comparatively trifling character of the early signs, the germ of syphilis betrays one of its most dangerous characteristics. The germ of pneumonia, for example, may be present on the surface of the body, in the mouth or elsewhere, for a long time, but the moment it gets a real foothold, there is an immediate and severe reaction, the body puts up a fight, and in ten days or so has either lost or won. The germ of syphilis, on the other hand, secures its place in the body without exciting very strenuous or wide-spread opposition. The body does not come to its own defense so well as with a more active enemy. The fitness of the germ of syphilis for long-continued life in the body, and the difficulty of marshaling a sufficient defense against it, is what makes it impossible to cure the disease by any short and easy method.

The First Sore or Chancre.—The primary lesion, first sore or chancre,[6] is the earliest sign of reaction which the body makes to the presence of the growing germs of syphilis. This always develops at the point where the germs entered the body. The incubation period ends with the appearance of a small hard knot or lump under the skin, which may remain relatively insignificant in some cases and in others grow to a considerable size. Primary lesions show the greatest variety in their appearance and degree of development. If the base of the knot widens and flattens so that it feels and looks like a button under the skin, and the top rubs off, leaving an exposed raw surface, we may have the typical hard chancre, easily recognized by the experienced physician, and perhaps even by the layman as well. On the other hand, no such typical lesion may develop. The chancre may be small and hidden in some out-of-the-way fold or cleft, and because it is apt to be painless, escape recognition entirely. In women the opportunity for concealment of a primary sore itself is especially good, since it may occur inside the vagina or on the neck of the womb. In men it may even occur inside the canal through which the urine passes (urethra). The name "sore" is deceptive and often misleads laymen, since there may be no actual sore—merely a pinhead-sized pimple, a hard place, or a slight chafe. The development of a syphilitic infection can also be completely concealed by the occurrence of some other infection in the same place at the same time, as in the case of a mixed infection with syphilis and soft ulcers or chancroids. Even a cold-sore on the mouth or genitals may become the seat of a syphilitic infection which will be misunderstood or escape notice.

[6] Pronounced shan'-ker.