The painless early sores associated with primary syphilis, and the associated oral lesions of secondary syphilis, can be easily missed in the mouth. Additionally, even the classic secondary syphilis rash on the body, palms, and soles of the feet can be subtle. This, combined with a lack of screening of high risk individuals, definitely contributes to its spread.
Syphilis can become a serious health concern, and it is worth taking preventative measures to protect yourself. Such measures may include using condoms or dental dams for oral sex, as well as practicing safe sex in general. Left undetected and untreated, syphilis can increase your risk of HIV and lead to systemic health problems. Also of concern for women is the possibility that a syphilis infection during pregnancy could lead to congenital syphilis, affecting their newborn. There has been a noticeable increase in congenital syphilis cases in recent years, and the condition can be fatal for the child if not caught and treated promptly.
Sources:
Ciesielsk et al.(October 22, 2004)"Transmission of Primary and Secondary Syphilis by Oral Sex - Chicago, Illinois, 1998-2002." MMWR 53(41):966-968
Syphilis-CDC Fact Sheet. (Accessed 2-18-09)
Syphilis and Men Who Have Sex With Men-CDC Fact Sheet. (Accessed 2-18-09)

