Although there are some external signs of syphilis (the initial ulcer, a rash and late signs of advanced disease), not everyone has obvious signs so care must be taken to avoid contact between genitals and body fluids until sexual partners have been tested and shown to be negative.
Wearing a condom during genital or anal intercourse and a dam during cunnilingus offers the best protection available. Avoid contact with anything that suggests it could be a syphilis rash or any sores near the genitalia, because these will be infectious.
Infection with syphilis is not catastrophic, but wasting time before seeking treatment can be. Anyone who finds themselves dealing with a case of syphilis must inform any and all sexual partners immediately, so prevent further cases and allow them to seek treatment if necessary.
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