Syphilis: Symptoms, Causes, and Treatments
Syphilis is a bacterial infection, primarily spread through sexual contact, that progresses through several stages, each with distinct symptoms. The initial stages, known as primary and secondary syphilis, often present with skin sores, rashes, and flu-like symptoms. After these stages, the infection enters a latent stage, where it remains in the body without causing any noticeable symptoms. If left untreated, syphilis can progress to the tertiary stage, causing severe damage to the heart, brain, blood vessels, and other organs, and in rare cases, can be fatal.
Impact and Scope of the Problem
Syphilis remains a global health issue, with WHO estimating 8 million new cases in 2022 among adults aged 15-49. The infection disproportionately affects key populations, including men who have sex with men. A particularly concerning trend is the increase in congenital syphilis, where an infected pregnant individual passes the disease to their child during pregnancy or childbirth, continues to contribute to neonatal deaths and serious health issues in newborns.
In recent years, syphilis cases have been on the rise in the United States. According to the Centers for Disease Control and Prevention (CDC), over 176,000 cases were reported in 2021, marking a 74% increase since 2017. This rise is observed across all age groups and genders, though men who have sex with men are disproportionately affected, accounting for 36% of all primary and secondary syphilis cases and nearly 47% of all male cases in 2021.
In 2021, over 2,800 cases of congenital syphilis were reported in the U.S., a 203% increase since 2017.
Despite the rising incidence, syphilis remains treatable and curable with antibiotics. Early detection and treatment are crucial to prevent the disease from progressing to stages that cause irreversible organ damage. While antibiotics can eliminate the infection at any stage, damage caused in the tertiary stage may be permanent.
Syphilis and HIV
People with syphilis are at a higher risk of acquiring HIV. Syphilis sores can make it easier for HIV to enter the body during sexual contact. It is important for individuals diagnosed with syphilis to also get tested for HIV and other sexually transmitted infections (STIs).
What Causes Syphilis and How Is It Transmitted?
Syphilis is caused by the bacterium Treponema pallidum. The primary mode of transmission is direct contact with a syphilis sore or rash during sexual activities, including vaginal, anal, and oral sex.
Syphilis can also be transmitted from an infected mother to her unborn child through the placenta during pregnancy or during childbirth, leading to congenital syphilis. Although transmission through blood transfusions is possible, this risk is minimized in the U.S. due to routine screening of donated blood.
It is important to note that syphilis cannot be spread through casual contact, such as sharing toilet seats, doorknobs, swimming pools, bathtubs, clothing, or eating utensils with an infected person.
The infection is most contagious during the primary, secondary, and early latent stages (within 12 months of infection). During the late latent and tertiary stages, syphilis is no longer contagious through sexual contact but can still be transmitted from a pregnant person to their fetus. Once treatment is complete and any sores have fully healed, syphilis can no longer be transmitted to others.
Symptoms of Syphilis
Syphilis progresses through several stages, each characterized by its own set of symptoms. Understanding these symptoms can help in early detection and treatment, which is crucial for preventing the disease from progressing to more severe stages.
Primary Syphilis
The first stage of syphilis, known as primary syphilis, typically presents symptoms between three to 90 days after exposure to the Treponema pallidum bacterium. The hallmark symptom of this stage is the appearance of a chancre, a firm, round, and usually painless sore at the site of infection. Chancres commonly develop on the penis, vulva, or vagina but can also appear on less expected areas such as the cervix, anus, rectum, lips, throat, hands, or other parts of the body. In some cases, multiple sores may appear. These sores generally heal on their own within three to six weeks, but the infection remains in the body. 
Secondary Syphilis
If left untreated, syphilis progresses to the secondary stage, which can begin about two weeks to three months after the initial sore appears. During this stage, symptoms can be more widespread and varied, including:
- Skin rash. This rash often does not itch and can cover a wide area or be localized to specific regions such as the palms of the hands or the soles of the feet.
- Mucous patches. These are sores that can develop in the mouth, on the tongue, or on the genitalia.
- Condylomata lata. Raised, gray or white lesions that form in moist areas like the mouth, genitals, anus, and armpits.
- Flu-like symptoms. These may include fever, sore throat, fatigue, muscle aches, and joint pain.
- Patchy hair loss: This can affect the scalp, eyebrows, or beard.
- Weight loss
- Headaches
- Swollen lymph nodes
In about 10% of cases, secondary syphilis can affect other organs, including the eyes, bones, joints, kidneys, liver, spleen, or the meninges (the membranes covering the brain and spinal cord). If untreated, the symptoms of secondary syphilis will generally resolve on their own within two to six weeks, but the infection will persist.
Latent Syphilis
Following the secondary stage, syphilis can enter a latent stage, where the infection remains in the body but does not produce symptoms. This stage can last for years or even decades and is divided into two stages.
- Early Latent Syphilis. This stage occurs within 12 months of the initial infection and is still considered contagious.
- Late Latent Syphilis. Occurring more than 12 months after infection, this stage is typically not contagious through sexual contact, although an infected pregnant person can still pass the disease to their fetus.
Tertiary (Late-Stage) Syphilis
Tertiary syphilis can develop five to 30 years or more after the initial infection in about 30% of untreated individuals. This stage can lead to serious complications that affect various organs and tissues throughout the body, including:
- Neurosyphilis. When the infection spreads to the brain or spinal cord, it can cause headaches, muscle weakness, personality changes, and memory problems.
- Cardiovascular Syphilis. This occurs when the infection affects the heart and blood vessels, particularly the aorta.
- Gummatous Syphilis. Characterized by the formation of rubbery growths known as gummas on the skin, bones, or internal organs.
At any stage of syphilis, the infection can affect the eyes and ears, leading to ocular syphilis or otosyphilis. Symptoms of these forms include:
- Ocular Syphilis. Eye pain, sensitivity to light, blurred vision, and potential loss of vision.
- Otosyphilis. Tinnitus (ringing in the ears), hearing loss, dizziness, vertigo, and balance problems.
Symptoms of Congenital Syphilis
Congenital syphilis occurs when a pregnant individual transmits the infection to their baby, which can result in severe complications such as stillbirth, preterm birth, miscarriage, low birth weight, or newborn death. Newborns with congenital syphilis may not show symptoms immediately, but when symptoms do appear, they can include:
- Bone abnormalities
- Anemia
- Enlarged liver and spleen
- Swollen lymph nodes
- Jaundice (yellowing of the eyes and/or skin)
- Skin rash
- Poor growth
- Vision problems, including blindness
- Hearing problems, including deafness
Early detection and treatment are vital in managing syphilis at any stage, particularly in preventing the severe outcomes associated with congenital syphilis.
Diagnosis of Syphilis
Diagnosing syphilis involves a combination of clinical evaluation, sexual history, physical examination, and laboratory testing. Since syphilis can be asymptomatic, especially in its early stages, testing is crucial for accurate diagnosis.
Laboratory Tests
Syphilis is caused by the bacterium Treponema pallidum. Laboratory tests can detect the presence of this bacterium directly through a microscope or indirectly through blood tests. Rapid tests are also available, providing results in minutes, which allows for immediate treatment initiation.
Congenital Syphilis Diagnosis
Diagnosing congenital syphilis is challenging as there are no specific tests for it. However, all infants born to mothers with syphilis should be examined for signs of the infection. This may include clinical examination, radiology, and laboratory tests at birth and during follow-up visits.
Treatment of Syphilis
Syphilis is treatable and curable with antibiotics. Early diagnosis and treatment are essential to prevent the infection from progressing to more severe stages.
Early-Stage Treatment
The early stage of syphilis is typically treated with a single injection of benzathine penicillin G (BPG). BPG is the first-line treatment for syphilis and the only treatment recommended by WHO for pregnant women with syphilis. For those who are allergic to penicillin, alternative antibiotics such as doxycycline, ceftriaxone, or azithromycin may be used under medical supervision.
Late-Stage Treatment
Later stages of syphilis, including latent and tertiary syphilis, require more doses of BPG, usually administered once a week for three weeks. Early and adequate treatment can prevent the severe complications associated with late-stage syphilis.
Treatment During Pregnancy
Treating syphilis during pregnancy is crucial to prevent the transmission of the infection to the baby. BPG is the recommended treatment during pregnancy and can effectively prevent congenital syphilis.
Prevention of Syphilis
Syphilis is a preventable disease. Taking certain precautions can significantly reduce the risk of infection.
- Condom Use. Consistent and correct use of condoms during vaginal, anal, and oral sex is one of the most effective ways to prevent syphilis. However, syphilis can still spread through contact with sores in areas not covered by a condom.
- Regular Testing. People at higher risk of syphilis, such as those with multiple sexual partners or those who are sexually active in high-prevalence areas, should get tested regularly. Pregnant women should be tested for syphilis at their first prenatal visit to prevent congenital syphilis.
- Partner Notification. If you are diagnosed with syphilis, it is important to notify your sexual partners so they can get tested and treated if necessary. This helps prevent the spread of the infection and protects others from potential complications.
Outlook for People with Syphilis
In its early stages, syphilis (whether primary, secondary, or early latent) is typically curable with the right antibiotic treatment. However, it’s important to note that even after successful treatment, reinfection can occur. This makes ongoing preventive measures and regular testing essential for maintaining health and preventing further transmission.
If left untreated, syphilis can advance to the tertiary stage, leading to severe health complications, such as damage to the heart, brain, and other vital organs. While antibiotics can eradicate the bacterial infection at this stage, any damage already done to organs or tissues may require additional medical care and could be irreversible.
To prevent spreading syphilis, individuals who have been diagnosed and are undergoing treatment should avoid sexual activity until their treatment is fully completed and follow-up tests confirm that the infection has been completely cleared.
Conclusion
Syphilis is a serious but preventable and treatable infection. Early detection and prompt treatment are key to avoiding the long-term health consequences of the disease. By staying informed, practicing safe sex, and getting regular screenings, you can protect yourself and others from syphilis and ensure that any infection is treated before it progresses. If you suspect you may have syphilis, seek medical advice promptly early intervention can make all the difference in your health and well-being.
FAQs About Syphilis
What is syphilis?
Syphilis is a bacterial infection that is primarily spread through sexual contact. It can also be passed from a pregnant mother to her baby, leading to congenital syphilis.
How is syphilis transmitted?
Syphilis is transmitted through direct contact with a syphilis sore during vaginal, anal, or oral sex. It can also be spread from an infected mother to her baby during pregnancy or childbirth.
Can syphilis be cured?
Yes, syphilis can be cured with antibiotics, typically with a single injection of penicillin in the early stages. However, it is important to get treated early to prevent complications.
Is syphilis preventable?
Yes, syphilis is preventable. Consistent and correct use of condoms during sexual activity can reduce the risk of transmission. Regular testing and prompt treatment of sexual partners also help in prevention.
What happens if syphilis is left untreated?
If left untreated, syphilis can progress to its tertiary stage, leading to serious health complications such as neurological disorders, cardiovascular problems, and even death.
How can I get tested for syphilis?
You can get tested for syphilis through a blood test at a healthcare provider’s office, clinic, or testing center. Rapid tests are also available and can provide results in a few minutes.
Can syphilis affect my baby during pregnancy?
Yes, syphilis can be passed from a mother to her baby during pregnancy, leading to congenital syphilis. This can cause serious health problems for the baby, including stillbirth, neonatal death, and lifelong disabilities. Pregnant women should be tested and treated for syphilis to prevent these outcomes.
