Syphilis

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Syphilis progresses in stages, with symptoms that differ from one stage of the disease to the next and from person to person. In some cases, the symptoms aren't noticeable and you may not know you have the disease until you're tested.

first  stageIn the first stage, known as primary syphilis, the characteristic symptom is a painless and highly infectious sore (or sores) with raised edges called a chancre.
The chancre shows up at the site of infection, usually about three weeks after you're exposed to the bacteria, though it may appear earlier or up to three months later.
Because the chancre may be inside your vagina or your mouth, you might never see it.
A chancre could also show up on your labia, perineum, anus, or lips, and your lymph nodes may be enlarged in the area where the sore develops.

If you get appropriate treatment at this stage, the infection can be cured. If you're not treated, the sore lasts three to six weeks and then heals by itself. However, the spirochetes are likely to continue to multiply and spread throughout the bloodstream. When this happens, the disease progresses to the next stage, called secondary syphilis.

secondary stageIn the secondary stage, syphilis can have a variety of symptoms that show up in the weeks or months after the sore first appeared, but again, they might not be noticeable.

Most people with secondary syphilis develop a non-itchy rash, commonly on their palms and soles, though it may also appear on other parts of the body.
You might also have lesions in your mouth and vagina, as well as painless but infectious wart-like sores in the genital area, flu-like symptoms, weight loss, and hair loss. The infection is still curable with treatment at this stage.
Without treatment, the symptoms generally clear up on their own within a few months, but the infection stays in your body. The bacteria continue to multiply during this latent phase and can cause very serious problems years later.

In fact, about 1 in 3 people who don't get proper treatment will progress to what's called tertiary syphilis.

tertiary syphilis
This late stage of the disease can develop up to 30 years after you were first infected and can cause serious heart abnormalities. Damaging and potentially lethal lesions can develop in your bones, on your skin, and in a host of organs. Fortunately, most people get treated early enough these days that very few end up with tertiary syphilis.
Syphilis can also infect your central nervous system – your brain and spinal cord. This is called neurosyphilis, and it can occur at any stage of the disease. Early on, it may cause problems like meningitis. Late neurosyphilis can lead to seizures, blindness, hearing loss, dementia, psychosis, spinal cord problems, and eventually death.