If there is neuritis from the virus it becomes intense and causes muscular contractions, paresis, and paralysis. The optic, auditory, and olfactory nerves may be attacked and destroyed. The nose also may be destroyed and it commonly caves in. The bones of the face are frequently attacked in the tertiary stage and they rot away. The tibia is diseased more frequently than the other long bones.

The heart is rarely injured, but when it is, the prognosis usually is bad. In a large number of cases death is sudden and unexpected. If the arteries are involved the prognosis again is bad, because the symptoms here do not show until [{313}] too late for effective treatment When the liver is the seat of gummata these may be cured in the early stage, but in the later stage the prognosis is unfavourable. Some forms of renal syphilis are remediable, but others are not, especially the interstitial kind.

Syphilis is transmitted to a child congenitally, not as a tendency or predisposition, but as an active contagion. It may come from the father, the mother, from both parents, or by direct infection.

The transmission from the father is the most frequent. The spermatozoa carry the infection to the maternal ovum. Down to the end of the secondary stage, and half through the intermediate period between the secondary and tertiary stages of syphilis, a father or mother may beget a child that will be infected with hereditary syphilis, a shivering, blasted, rotten little wretch for whom a quick death is the greatest imaginable blessing, and it usually gets this blessing. In the acute stage of a virulent syphilis the disease is most likely to be transmitted; but sometimes, though rarely, a father that has been free from all symptoms of syphilis for many years may beget a child that is born with a virulent hereditary form of the disease.

Infection by the mother is more certain and more harmful than that from the father, because the intrauterine life of the child is poisoned throughout its course. Two-thirds of the cases of hereditary syphilis die either by abortion, or if they live to term they die shortly after delivery. If the mother is infected during the first eight months of pregnancy the child will nearly always be syphilitic, but if she is infected after the eighth month the child may escape.

If at the moment of conception both parents have the disease the child will almost certainly take it, and this infection will cause its death. In a series observed by Fournier, 28 per centum of the cases caused by paternal infections died and 37 per centum showed the luetic taint; in the cases caused by maternal infection 60 per centum died, and 84 per centum had syphilitic lesions; in the mixed heredity, that is when both the father and mother were luetic, 68.5 per centum died and 92 per centum were born syphilitic. When a child [{314}] is first infected at delivery the case is not technically classed as hereditary syphilis.

During the first year after the father or mother has taken syphilis the probability of infecting the child is the greatest. In the third year the liability of infecting the child is lessened, but present. In a series of 562 cases of hereditary syphilis observed by Fournier, 60 children, over 10 per centum, were infected more than six years after the primary parental infection. Carefully observed cases have been exceptionally found where infection of the child has occurred in the fifteenth and even the twentieth year after the original parental lesion. Fournier reports the case of one woman that had nineteen consecutive stillbirths from syphilis.

Mild parental syphilis may transmit hereditarily the most malignant type of the disease, and very virulent parental infection may result in a comparatively mild infection of the child, if any infection by syphilis may be called mild. That the parent shows no symptoms from an old infection is no proof that he or she is cured, or that the child may not be infected.

With proper treatment of the mother the infantile mortality in hereditary syphilis is reduced from 59 per centum to 3 per centum, and the children that are born living are not unfrequently free from syphilis. When a woman is infected at the conception of her child miscarriage takes place before the child is viable, from the first to the sixth month; later other miscarriages occur; later still, living but syphilitic children are born, of whom one-fourth die within the first six months; finally she may have children that are not infected.

If a syphilitic man has been properly treated he may, after four years, beget healthy children, and he commonly does, but he may be the father of syphilitic children. Syphilitic women properly treated may, after about six years from infection, bring forth healthy children, and they commonly do, but not always.