General Course and Character of the Dis Syphilis bears a certain resemblance to the infectious fevers, as smallpox, measles, etc., in its incubation, mode of development and the appearance of a characteristic eruption. In the majority of cases the phenomena of syphilis develop with a certain order or regularity which admits of its division into periods or stages, known as the primary, secondary and tertiary stages. •After the introduction of the virus there is no appreciable evidence of its action during a period more or less prolonged, from two to five weeks, on the average 28 days. This period is termed the period of primary in cubation or the incubation of the chancre. At the expiration of this period there appears at the point of entrance of the virus the chancre, which is termed the initial or primary lesion of syphilis. This primary lesion constitutes for a time the sole sign, the unique expression of the disease. After the appearance of the chancre there ensues a period of six to seven weeks, termed the period of secondary incubation. During this period, the lymphatic glands near est the chancre undergo an indolent enlarge ment, constituting what is termed the bubo of syphilis. After the second incubation the dis ease is said to become constitutional, although it is not definitely known at what precise time generalization of the virus takes place. Not infrequently there is, during this period, some evidence of constitutional disturbance—head ache, neuralgia and febrile disturbance, more or less pronounced — which ushers in what are recognized as the constitutional signs of syphi lis, in the shape of eruptions upon the cuta neous surface or the mucous membranes.
The secondary stage of syphilis is usually from 18 months to two and a half years in duration. The secondary eruptions are not continuously present, but come out in successive crops. The completion of this stage may mark the definite end of the disease, or there may succeed the tertiary stage, characterized by the appearance of gummatous formations which may affect the sub-cutaneous tissues, the peri osteum, the bones and the internal organs of the body. The duration of this stage is practi cally indefinite. The tertiary lesions may con tinue to recur for 5, 10 to 15 years, or even dur ing the lifetime of the individual. This division of syphilis into stages is somewhat artificial. It does not always pursue this regular and me thodic course with an orderly procession of sec ondary and tertiary lesions; there is not always a sharp limitation between the stages. Second ary manifestations may continue to recur for several years.
Syphilis, as we comprehend it to-day, has a much graver significance in its relation to the health of the individual than was formerly sup posed. Our conception of the range of its pathological action has been gradually enlarged with increasing knowledge of the vast com plexity and far-reaching character of its morbid processes. While it was formerly known that syphilis was a constitutional disease and capable of causing changes in the internal organs, these systemic complications were regarded as few in number and of only occasional occurrence.
The secondary manifestations visible upon the surface of the body were thought to constitute practically the entire expression of the disease. At the present day, these secondary manifesta tions are regarded as of subsidiary importance, since they rarely compromise the integrity of any important organ. The tertiary manifesta tions of the disease—cerebral, spinal, vascular, .ocular, pulmonary, intestinal, hepatic and renal affections — constitute the chief significance, as well as the individual danger of the disease. The tertiary lesions of the brain and cord oc cupy the first rank in frequency as well as in gravity. Of all the menaces to the life and health of the individual from syphilis, lesions of the nerve centres are the most to be feared. The pathological field of syphilis has been greatly enlarged by the inclusion of a group of affections badly termed parasyphilitic, which, though of syphilitic origin and nature, are extremely refractory to specific treatment and practically incurable. As types of this group may be mentioned locomotor ataxia and general paralysis. It has been stated that every hemi plegia occurring in a man less than 40 years of age addicted to alcohol or affected with lesions of the circulatory system is, in nine cases out of 10, of syphilitic character. Practically all cases of paresis and tabes dorsalis are due to syphilis, • and the spirochete has been found in the brain spinal cord in these diseases.
Syphilitic Heredity, From a strictly socio biological standpoint, the hereditary conse quences of syphilis are of the greatest signifi cance. Its pernicious effects upon the offspring give to syphilis an especial importance as a factor in the degeneration and depopulation of the race. Syphilis is recognized as the per fected type of a hereditary disease. No other disease is so susceptible of hereditary transmis sion, so pronounced in its influence and so de structive to the offspring. The hereditary in fluence of most other diseases is manifest in the transmission to the offspring of a constitu tional protoplasmic state, characterized by a feeble organization and diminished resistance to disease. In tuberculosis and leprosy, for example, the influence of heredity is limited to the creation of a predisposition to disease, from an enfeebled capacity of resistance of the or ganism, which renders it readily susceptible to the action of the germs of disease. In syphilis there is a direct transmission of the specific qualities contained in the sperm or germinal cells, with the result that the normal processes of nutrition are vitiated and the produce of conception is blighted in its development or destroyed. No disease has such a murderous influence upon the offspring as syphilis.