SYPHILIS

AGENT OF DISEASE

Syphilis is caused by the spirochete Treponema pallidum.

WORLDWIDE DISTRIBUTION

Occurrence is worldwide. The estimated annual incidence in 1995 was 12 million; the greatest number was in Asia, followed by subSaharan Africa.

SYMPTOMS

Syphilis is classified into stages that reflect the degree of infectivity and progression of the disease: primary, secondary, early latent, late latent, and tertiary.

The first stage, primary syphilis, is characterized by the appearance of a painless ulcer, called a chancre, about 3 weeks (range: 10- 90 days) after sexual contact with an infected person. Syphilitic genital ulcer increases the risk of HIV. The chancre gradually disappears, and in about one-third of untreated cases of primary syphilis there is progression to secondary syphilis.

Secondary syphilis occurs about 4-6 weeks after primary syphilis and is characterized by a rash involving the palms and soles, accompanied by fever, sore throat, hair loss and swelling of lymph nodes. In about one-third of untreated secondary infections there is progression to latent infection.

Latent (hidden) syphilis occurs when the bacteria remain in the body even though the patient has no symptoms. It is subdivided into early latent and late latent stages. Individuals who have had syphilis for less than a year and are asymptomatic are classified as having early latent syphilis; they may have recurrences of lesions of the skin and mucous membranes, and are potentially infectious to their contacts.

In about one-third of untreated cases the disease will progress to tertiary syphilis, when the bacteria invade the brain, nerves, eyes, heart, blood vessels, liver, bones or joints.

Syphilis infection in the fetus can cause miscarriage, stillbirth or prematurity. An infant with congenital syphilis may be born without any symptoms, but will develop them within the first few weeks of life if not treated immediately. Early manifestations may include enlarged liver, enlarged spleen, swollen lymph glands, skin and mouth sores, inflammation of bones, and anemia. Late manifestations after 2 years of age may involve the brain (with hearing loss, mental retardation or seizure), eyes, bones, joints, teeth and skin.

For surveillance purposes, syphilis is classified as early symptomatic syphilis (primary and secondary syphilis), early latent syphilis, syphilis other (late latent and tertiary) and congenital syphilis.

PERIOD OF COMMUNICABILITY

An infected individual can transmit the infection to his/her sexual partner usually during the primary, secondary and early latent stages of the disease. Individuals can be considered non-infectious after the resolution of open lesions with appropriate antibiotic therapy. Congenitally infected newborns can be rendered non-infectious once appropriate antibiotic therapy has been administered for at least 24 hours.

HOW IT IS TRANSMITTED

Syphilis is transmitted by sexual contact with an infected individual in the primary, secondary or early latent stage of the disease. It can be transmitted from pregnant women to the babies they are carrying. Transmission can also occur through transfusion of unscreened blood or direct inoculation.

PREVENTION/CONTROL

• Routine prenatal serologic screening for syphilis and appropriate management of infection in pregnant women
• Early diagnosis and treatment
• Partner notification