Syphilis is a reemerging infectious disease in the United States as it has made a troubling comeback after being on consistent decline throughout the '90s and reaching an all-time low in 2000. However, since the year 2000, the rates have been increasing, reaching from 2.7 to 3.0 cases per 100,000 of population between 2004 and 2005.

The disease has been increasing most in men who have sex with men (MSM). Federal health officials estimated that in recent years more than half of primary and secondary stages of syphilis, the stages at which syphilis is most infectious, have occurred among MSM. However, most recently concerns have been raised about an increase in cases among women also.

Syphilis is spread from person to person by direct sexual contact with an infected person. The infected person is most likely to transmit the infection when syphilitic sores and/or rashes are present. Initial sores usually occur at the site of primary contact, mainly on the external genitals, vagina, anus or rectum. Sores can also be on the lips and in the mouth.

Thus transmission occurs during vaginal, anal or oral sex. An infected pregnant woman can also pass the disease to her unborn child. Syphilis cannot be spread by contact with toilet seats, door knobs, swimming pools, hot tubs, bathtubs, shared clothing or eating utensils.

Symptoms of syphilis usually appear 3-4 weeks after infection, although they may start as early as one week or as late as 13 weeks after initial infection. Symptoms vary by stage of the disease.

In the primary stage, a painless sore (chancre) appears at the site where the syphilis bacterium first entered the body—typically the penis, vulva or vagina. The chancre may also appear on the anus, rectum, lips, tongue, throat, cervix, fingers, or, rarely, other parts of the body. The chancre is usually round, firm, does not bleed and is painless. About half of infected women and one-third of infected men are unaware of it. The chancre usually heals by itself in 3 to 12 weeks and the person may look completely healthy. However, the syphilis is not gone, and without treatment the disease progresses to the next stage, called secondary syphilis.

The secondary stage usually begins with a skin rash that may appear several weeks after the chancre is healed, or for some infected people the chancre may still be healing. The rash usually does not itch or hurt and can have many different appearances. The characteristic rash of secondary syphilis appears as rough red or reddish-brown spots on the palms or soles. Sometimes rashes are so faint that they are not noticed. Because in this stage the syphilis spreads throughout the body through blood circulation, it also can cause a wide range of other general symptoms such as fever, swollen lymph glands, sore throat, patchy hair loss, headaches, weight loss, muscle aches and fatigue. The signs and symptoms of secondary syphilis will resolve with or without treatment, but without treatment, the infection will progress to the latent and late stages of disease. During the latent stage of syphilis, the infection remains in the body but no symptoms occur. This stage may last for years to decades—or for the rest of the person's life.

In the late stages of syphilis (referred sometimes as tertiary or third stage syphilis), syphilis is not infectious but symptoms ranging from mild to severely debilitating can occur. Many internal organs, including the brain, nerves, eyes, heart, blood vessels, liver, bones and joints can be damaged at this stage. This internal damage may show up many years later. Signs and symptoms of the late stage of syphilis include difficulty coordinating muscle movements, paralysis, numbness, dementia, bone pain, gradual blindness, chest pain, heart failure or even death.

A typical chancre or a rash on the palms and soles usually leads a doctor to suspect syphilis. In this case, the doctor may obtain material from a chancre or rash and examine it under the microscope to see if there are spiral-shaped bacteria.

A definitive diagnosis is based on the results of syphilis screening blood laboratory tests such as the Venereal Disease Research Laboratory (VDRL) or the rapid plasma reagin (RPR) test. These tests may be falsely negative in the first few weeks of primary syphilis or can come back falsely negative because of other diseases. Hence, the positive test usually is confirmed with a second more specific blood test that measures antibodies to syphilis bacteria. Successful treatment will lead to negative screening tests but the second confirmatory test will remain positive for an indefinite period of time. In the late stage of syphilis when the brain may have been affected, a spinal tap can be used in addition to the blood test to obtain spinal fluid for antibody testing.

• Abstain from sex or be in a monogamous long-term relationship with a partner who has been tested and not infected.
• Use condoms.
• Pregnant women need to get a prenatal blood test, as untreated syphilis in a pregnant woman can infect and possibly kill her developing baby.

Syphilis cannot be prevented by washing the genitals, urinating or douching after sex.