Syphilis is a sexually transmitted infection (STI) that has been around for centuries, but cases are increasing: In 2020, there were more than 130,000 new cases in the United States.
After syphilis is contracted, it goes through four stages: primary, secondary, latent, and tertiary.
It is important for sexually active people to understand signs and symptoms of syphilis.
Prompt treatment is essential if any of them develop to prevent long-term complications.
In this article, I’ll talk about the causes of syphilis, outline its stages, and explore the infection’s symptoms, treatment, and when it’s contagious.
I’ll also talk about some precautions and preventive measures, and tell you when to see your doctor.
What Causes Syphilis
Syphilis is a sexually transmitted infection (STI) caused by Treponema pallidum, a type of bacteria.
It is caused by contact with someone who has sores (known as chancres) or an active syphilis infection in the primary or secondary stage.
Syphilis may be contracted during vaginal, anal, or oral sexual contact.
Pregnant people can also pass syphilis to infants during childbirth.
Syphilis Stages Guide
Syphilis has four stages.
The sooner it is treated, the better a patient may fully recover.
The first symptom after exposure to syphilis may appear within 10-90 days, but 21 days is most common.
The first sign is usually one or more sores, known as chancres.
A chancre can look like a small cut or ingrown hair.
They are typically painless.
Chancres tend to be small, firm, and round.
Outbreaks typically resolve within 3-6 weeks, with or without treatment.
Syphilis does not resolve without antibiotic treatment, even after chancres are gone.
Immediately after the primary stage, or sometimes weeks or months later, a rough, red rash appears on the body.
Sometimes it is isolated to one spot, while at other times it covers most of the body’s surface.
The rash is not painful or itchy.
It may also be pale or unnoticeable.
Red or brown spots may also develop on the hands and soles of the feet.
Lesions that are white or gray may form in the armpits, groin, mouth, or nose.
Other secondary stage symptoms of syphilis include:
- Hair loss
- Sore throat
- Swollen glands
Symptoms will resolve on their own, with or without treatment, in 4-6 weeks.
A person remains infected with syphilis even after symptoms are gone unless they are treated with antibiotics.
Once the initial two stages have resolved, most people are no longer contagious with syphilis, but still remain infected.
Symptoms often disappear completely.
Without treatment, more serious health consequences can develop over time.
Sometimes referred to as late stage syphilis, around 15% of people who are infected will progress to this stage.
It can occur 10-30 years after infection.
In this phase, the infection causes damage to vital organs like the brain, heart, eyes, and ears.
It also affects both nervous and muscular systems.
Symptoms that may appear during this phase include:
- Blindness or vision problems
- Poor muscular control or coordination
When is Syphilis Contagious?
Syphilis is contagious during the first two phases of the infection, typically when other symptoms are present.
It is transmitted during sexual contact
Less commonly, it can potentially be transmitted through direct contact with an active oral lesion, such as while kissing.
Pregnant people may also pass syphilis to babies during pregnancy or birth.
Syphilis is not contagious by using shared surfaces (toilets, tubs, showers, clothing), utensils, or swimming pools and hot tubs.
Syphilis cannot come back on its own after someone has been treated and cured.
You can get reinfected if you are exposed to syphilis again.
How common is syphilis?
Syphilis remains a common sexually transmitted infection around the world, with 6 million new cases each year.
It affects people of all genders and is transmitted by any type of sexual contact.
Congenital syphilis, which is passed to infants from infected mothers, is a worldwide health concern.
In 2020, there were more than 2,000 cases of congenital syphilis in the United States alone.
Who’s more prone to contracting syphilis?
Anyone who has vaginal, anal, or oral sex can contract syphilis if their partner is infected.
People who may be at increased risk include those who:
- Have multiple partners (or have a partner who has multiple partners)
- Don’t use condoms consistently or properly
- Have HIV
People with penises who have sexual contact with other people with penises are at a higher risk of contracting syphilis, but it can affect any gender or type of sexual contact.
Primary stage symptoms of syphilis include:
- Small, round, painless sores anywhere on the body (commonly around the anus, groin, or mouth)
- Enlarged lymph nodes around the groin
Secondary stage syphilis symptoms can include:
- Small, red or brown sores on the skin
- A red or pale red rash
- Swollen lymph nodes
- Sores in the mouth, vagina, or anus
- Hair loss
- Muscle aches
There are no symptoms for the latent stage of syphilis.
A person may still be contagious early in the latent phase.
Symptoms of syphilis in the tertiary stage can vary based on where the infection affects the body.
It can include:
- Heart problems
- Brain problems
- Nervous system problems
- Muscular problems
Tertiary stage syphilis can result in permanent organ damage or be fatal.
People who are in the primary or secondary stage of syphilis are typically diagnosed based on symptoms.
A healthcare provider will perform a physical examination and may run tests to verify the bacterial cause of the infection.
Some blood tests may also be used to confirm a diagnosis.
Regardless of the stage, syphilis is typically treated with antibiotics.
Penicillin is a first-line treatment.
People who are allergic to penicillin will be treated with a different antibiotic.
If you or a partner are being treated for syphilis, all sexual contact should be avoided until the treatment is complete to avoid continuing to spread the infection.
You can be reinfected with syphilis after being cured.
In many cases, if one partner is diagnosed with syphilis, sexual partners will be tested and may be treated if they were exposed.
Precautions and Prevention
There are many ways to decrease the risk of exposure to syphilis.
- Get tested.
- Have new partners get tested before having sexual contact with them.
- Avoid sexual contact with someone who has syphilis or signs of other sexually transmitted diseases.
- Use condoms properly and consistently. It is still possible to contract syphilis with proper condom use if chancres are present.
- Use dental dams for oral sexual contact.
- Use latex gloves for manual sexual contact.
If you have been diagnosed with syphilis, let current and past sexual partners know so they can be tested and receive treatment, if necessary.
When to See a Doctor
If you are sexually active and notice signs or symptoms of sexually transmitted infections, see a medical provider for an accurate diagnosis and proper treatment.
Signs that may be associated with sexually transmitted infections include:
- Any type of sore, wart, bump, or lump around the genitals, anus, or groin
- Any type of sore or lesion in or around the mouth
- A rash that lasts more than 1-2 days
- A rash on the hands or feet
If you are concerned about syphilis or other sexually transmitted infections, you can chat with a K Health doctor from the comfort of your own home and get private, accurate, prompt medical care.
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Frequently Asked Questions
K Health articles are all written and reviewed by MDs, PhDs, NPs, or PharmDs and are for informational purposes only. This information does not constitute and should not be relied on for professional medical advice. Always talk to your doctor about the risks and benefits of any treatment.
K Health has strict sourcing guidelines and relies on peer-reviewed studies, academic research institutions, and medical associations. We avoid using tertiary references.
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An update on the global epidemiology of syphilis. (2018).
The great imitator revealed: syphilis. (2019).
Syphilis staging and treatment. (2018).