Syphilis cases among men who have sex with men (MSM) in San Diego County outnumber heterosexual cases, according to data compiled by San Diego County Health and Human Services Agency. Out of a total of 218 reported cases in 2004, 150 were MSM – that’s 68 percent of all cases.

It hasn’t always been that way, according to Dr. Robert Gunn, STD control officer in the Division of STD and Hepatitis Prevention Services branch of the County of San Diego Health and Human Services Agency.

“When I first got here in the early ’90s there was a lot of heterosexual syphilis, 300 and 400 cases a year, and it was in African-American population,” said Gunn.

Gunn said that in the mid-1990s, cases of syphilis came down to low levels; around 25 cases a year. Then from 2001 to 2002, Gunn noticed a rise in gay men who had contracted the disease and he attributed that rise to the HIV epidemic, speculating that HIV-positive men would pair up and have unprotected sex with each other.

“A lot of our cases are HIV infected – like 50 percent or more,” Gunn said. “We think it’s gay men [who are] HIV infected who have abandoned any safe sexual behavior practice.”

Syphilis, an STD caused by a bacterium called treponema pallidum, has four stages. In the first stage, primary syphilis, the infection causes an ulcer at the site of the infection, called a chancre. It can appear anywhere from 10 days to three months after exposure, but generally appears within two to six weeks. The incubation period is around three weeks.

Since the chancre may be painless and may occur inside the body in the throat, rectal canal or under the foreskin on the penis, it may go unnoticed. The fragile syphilis bacterium spreads from the initial ulcer of an infected person to the skin or mucous membranes of the mouth, genital area or the anus of another sexual partner. If left untreated, syphilis bacteria can severely damage the body’s organs as it travels throughout the body.

The second stage, usually marked by a skin rash that lasts a few weeks, may cover the entire body, including the palms and soles of the feet. Other symptoms in this stage may include fevers, fatigue, headaches and a sore throat, as well as patchy hair loss and swollen lymph glands. If untreated, syphilis may lapse into a latent stage where it is no longer contagious and no symptoms appear. About one-third of those who have secondary syphilis progress to another stage called tertiary syphilis, in which the bacteria damage the heart, eyes, brain, nervous system, bones, joints, or almost any other part of the body. This stage can last for years, sometimes decades.

The final stage, called late syphilis, can result in mental illness, blindness, other neurological problems, heart disease and death.

Syphilis is usually treatable with penicillin, which can be administered by injection or a pill. Other antibiotics are used for patients who have allergies to penicillin. A person is usually not contagious 24 hours after beginning antibiotic therapy.

Since the early symptoms of syphilis can be mild and often unnoticeable, many people do not seek treatment when they first become infected, or they may think they are suffering from something else. Syphilis has sometimes been called “the great imitator” because its early symptoms are similar to those of many other diseases.

Gunn noted that if the trend of the last first four months continues, the county estimates approximately 300 cases to occur in San Diego this year.

Call the San Diego County STD clinic at (619) 692-8550 for more information about getting tested for syphilis or any other STD.