Syphilis is a sexually transmitted infection (STI) caused by a type of bacteria known as Treponema pallidum. In 2016, more than 88,000 cases of syphilis were reported in the United States, according to the Centers for Disease Control and Prevention. The rate of women with syphilis has been declining in the United States, but the rate among men, particularly men who have sex with men, has been rising.
The first sign of syphilis is a small, painless sore. It can appear on the sexual organs, rectum, or inside the mouth. This sore is called a chancre. People often fail to notice it right away.
Syphilis can be challenging to diagnose. Someone can have it without showing any symptoms for years. However, the earlier syphilis is discovered, the better. Syphilis that remains untreated for a long time can cause major damage to important organs, like the heart and brain.
Syphilis is only spread through direct contact with syphilitic chancres. It can’t be transmitted by sharing a toilet with another person, wearing another person’s clothing, or using another person’s eating utensils.
The four stages of syphilis are:
Syphilis is most infectious in the first two stages.
When syphilis is in the hidden, or latent, stage, the disease remains active but often with no symptoms. Tertiary syphilis is the most destructive to health.
The primary stage of syphilis occurs about three to four weeks after a person contracts the bacteria. It begins with a small, round sore called a chancre. A chancre is painless, but it’s highly infectious. This sore may appear wherever the bacteria entered the body, such as on or inside the mouth, genitals, or rectum.
On average, the sore shows up around three weeks after infection, but it can take between 10 and 90 days to appear. The sore remains for anywhere between two to six weeks.
Syphilis is transmitted by direct contact with a sore. This usually occurs during sexual activity, including oral sex.
Skin rashes and a sore throat may develop during the second stage of syphilis. The rash won’t itch and is usually found on the palms and soles, but it may occur anywhere on the body. Some people don’t notice the rash before it goes away.
Other symptoms of secondary syphilis may include:
These symptoms will go away whether or not treatment is received. However, without treatment, a person still has syphilis.
Secondary syphilis is often mistaken for another condition.
The third stage of syphilis is the latent, or hidden, stage. The primary and secondary symptoms disappear, and there won’t be any noticeable symptoms at this stage. However, the bacteria remain in the body. This stage could last for years before progressing to tertiary syphilis.
The last stage of infection is tertiary syphilis. According to the Mayo Clinic, approximately 15 to 30 percent of people who don’t receive treatment for syphilis will enter this stage. Tertiary syphilis can occur years or decades after the initial infection. Tertiary syphilis can be life-threatening. Some other potential outcomes of tertiary syphilis include:
- mental illness
- memory loss
- destruction of soft tissue and bone
- neurological disorders, such as stroke or meningitis
- heart disease
- neurosyphilis, which is an infection of the brain or spinal cord
During the secondary stage of syphilis, people develop red or reddish-brown bumps or patches, and they are very infectious at this point.
If you think you might have syphilis, go to your doctor as soon as possible. They’ll take a blood sample to run tests, and they’ll also conduct a thorough physical examination. If a sore is present, your doctor may take a sample from the sore to determine if the syphilis bacteria are present.
If your doctor suspects that you’re having nervous system problems because of tertiary syphilis, you may need a lumbar puncture, or spinal tap. During this procedure, spinal fluid is collected so that your doctor can test for syphilis bacteria.
If you’re pregnant, your doctor might screen you for syphilis because the bacteria can be in your body without you knowing it. This is to prevent the fetus from being infected with congenital syphilis. Congenital syphilis can cause severe damage in a newborn and can even be fatal.
Primary and secondary syphilis are easy to treat with a penicillin injection. Penicillin is one of the most widely used antibiotics and is usually effective in treating syphilis. People who are allergic to penicillin will likely be treated with a different antibiotic, such as:
If you have neurosyphilis, you’ll get daily doses of penicillin intravenously. This will often require a brief hospital stay. Unfortunately, the damage caused by late syphilis can’t be reversed. The bacteria can be killed, but treatment will most likely focus on easing pain and discomfort.
During treatment, make sure to avoid sexual contact until all sores on your body are healed and your doctor tells you it’s safe to resume sex. If you’re sexually active, your partner should be treated as well. Don’t resume sexual activity until you and your partner have completed treatment.
The best way to prevent syphilis is to practice safe sex. Use condoms during any type of sexual contact. In addition, it may be helpful to:
- Use a dental dam (a square piece of latex) or condoms during oral sex.
- Avoid sharing sex toys.
- Get screened for STIs and talk to your partners about their results.
Syphilis can also be transmitted through shared needles. Avoid sharing needles if using injected drugs.
Pregnant mothers and newborns
Mothers infected with syphilis are at risk for miscarriages, still births, or premature births. There’s also a risk that a mother with syphilis will pass the disease on to her fetus. This is known as congenital syphilis.
Congenital syphilis can be life-threatening. Babies born with congenital syphilis can also have the following:
- developmental delays
- swollen liver or spleen
- infectious sores
If a baby has congenital syphilis and it isn’t detected, the baby can develop late stage syphilis. This can cause damage to their:
People with syphilis have a significantly increased chance of contracting HIV. The sores the disease cause make it easier for HIV to enter the body.
It’s also important to note that those with HIV may experience different syphilis symptoms than those who don’t have HIV. If you have HIV, talk to your doctor about how to recognize syphilis symptoms.
The first stage of syphilis can easily go undetected. The symptoms in the second stage are also common symptoms of other illnesses. This means that if any of the following applies to you, consider getting tested for syphilis. It doesn’t matter if you’ve ever had any symptoms. Get tested if you:
- have had condomless sex with someone who might have had syphilis
- are pregnant
- are a sex worker
- are in prison
- have had condomless sex with multiple people
- have a partner who has had condomless sex with multiple people
- are a man who has sex with men
If the test comes back positive, it’s important to complete the full treatment. Make sure to finish the full course of antibiotics, even if symptoms disappear. Also avoid all sexual activity until your doctor tells you that it’s safe. Consider getting tested for HIV as well.
People who have tested positive for syphilis should notify all of their recent sexual partners so that they can also get tested and receive treatment.
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