Transmission

The most prevalent mode of transmission is by sexual contact; infection by other means is possible, but its occurrence depends upon an open wound or lesion to permit invasion of the organisms. A person with syphilitic sores has an increased chance of contracting AIDS from an infected partner. An infected mother can transmit the disease to her fetus; 25% of such pregnancies end in stillbirth or death of the infant, and another 40% to 70% will result in a baby with congenital syphilis, which, if untreated, can progress to late-stage syphilis and cause serious damage to the brain and other organs.

Symptoms

The development of syphilis occurs in four stages. The primary stage is the appearance of a painless chancre at the site of infection (often internal) about 10 days to 3 months after contact. There are no other symptoms, and the chancre disappears with or without treatment.

The secondary stage usually begins 3 to 6 weeks after the chancre with a rash over all or part of the body. Active bacteria are present in the sores of the rash. Headache, fever, fatigue, sore throat, patchy hair loss, and enlarged lymph nodes may be present. The signs of the secondary stage will disappear with or without treatment, but may reappear over the next 1 to 2 years.

Untreated syphilis then goes into a noncontagious latent period. Some people will have no more symptoms, but about one third will progress to tertiary syphilis, with widespread damage to the heart, brain, eyes, nervous system, bones, and joints. Late syphilis can result in mental illness, blindness, severe damage to the heart and aorta, and death.

Neurosyphilis, infection of the nervous system, frequently occurs in the early stages in untreated patients. There may be no symptoms, mild headache, or severe consequences such as seizures and stroke. Its treatment and course are complicated by concomitant HIV infection.

Diagnosis and Treatment

Diagnosis is made by symptoms, blood tests (required by many states before issuing marriage licenses), and microscopic identification of the bacterium. Until the advent of penicillin in the 1940s, treatment for syphilis was with mercury, arsenic, and bismuth. Penicillin is the antibiotic of choice for all stages of syphilis treatment, but penicillin-resistant organisms have complicated treatment of the disease. Even late-stage syphilis can be cured, but damage that has already occurred cannot be reversed. Despite available treatment, the incidence of syphilis in the United States was on the rise until 1990. Since then it has declined sharply, from 20 to just 2.1 cases per 100,000 people from 1990 to 2000. Federal health experts have attributed the decline to prevention efforts, including those intended to curtail the spread of AIDS. Since 2000, however, the number of syphilis cases has risen.

See also Ehrlich, Paul.

Sexually transmitted disease caused by the spirochete Treponema pallidum. Without treatment, it may progress through three stages: primary, characterized by a chancre and low fever; secondary (weeks to months later; only half of those infected display symptoms), with a skin and mucous-membrane rash, lymph node swelling, and bone, joint, eye, and nervous system involvement; and tertiary. The tertiary stage follows a latency period that can last years, and only one-fourth of those infected display tertiary symptoms. These can be benign or incapacitating and even fatal; almost any part of the body may be attacked. Syphilis can spread to a fetus from an infected mother. Other species of Treponema cause similar but milder, nonsexually transmitted forms of syphilis (see yaws). Several blood tests can detect syphilis, even during latency. Antibiotic treatment is effective.

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