The initial stage of the disease is called primary syphilis. There's usually just one ulcer, which appears 10 to 100 days (on average, one month) after infection. At first, it appears as a red dome and is where the bacteria initially multiply. It rapidly erodes to become a painless ulcer called a chancre (pronounced "shanker"). The chancre typically clears up and heals in a month or two whether the person is treated for the disease or not. A person is contagious during primary syphilis.
If the person is not treated, however, the bacteria can eventually enter the bloodstream and be carried to many parts of the body. This happens in about 25% of people who do not receive treatment for their primary syphilis. A rash can develop during this stage. It is typically seen about 6 weeks to 3 months after the chancre forms and, in some cases, can occur even though the chancre has not fully healed. The rash can get steadily worse over the next 2 months. Round red or brown spots appear on the chest, arms, and legs. What is particularly unusual about this rash is that it can also be found on the palms of the hands and soles of the feet. The rash can remain as red spots, or become pustular or scaly, but it is usually not very itchy. The rash may clear up only to be replaced by another.
There can also be flu-like symptoms such as headache, fatigue, and a mild fever. The bacteria can also get into the brain and cause meningitis. The person may experience hearing loss, balance problems, visual changes, and bone pain. Some people show signs of anemia and jaundice. This syndrome is called secondary syphilis and it can come and go for a year or two. For as long as the rash is present, a person with secondary syphilis is contagious.
In many people, syphilis stops there, even if it's not treated. The bacteria remain but they cause no symptoms and don't emerge to infect others. This is called latent syphilis. It may remain inactive forever, or may become active again years later.
People who aren't treated during the primary stage have a 1 in 3 chance of developing chronic tertiary syphilis. The bacteria retreat deep into the body and are no longer contagious, but syphilis can reappear decades after the last rash of secondary syphilis. The disease poses a grave threat to the internal organs, including the brain, heart, blood vessels, and bones. Syphilis can lead to death if it is not treated.
Complications of tertiary syphilis include:
- brain damage: Depending on which part is damaged, symptoms could range from motor effects (such as tremors) to mood disorders (such as having delusions of grandeur). Muscle weakness, pain, decreased muscle coordination, and loss of movement of the limbs are possible.
- heart and blood vessel damage: Syphilis has a particular tendency to damage the walls of the aorta, the body's biggest artery, which can lead to an aneurysm. This syndrome usually appears 10 to 25 years after the initial infection.
- damage to the retina and the vital nerves and blood vessels at the back of the eye: Syphilis usually attacks both eyes. If left untreated, irreversible eye damage that may result in blindness can develop. Again, this can happen many years after the original infection.
These are just some of the most likely organs to be damaged. However, symptoms should not become this severe, since syphilis can be cured in a few days at the outset. It can be a subtle disease, however, and can go unnoticed during the primary stage.