Syphilis Is Making a Big Comeback. What You Should Know.

April 12, 2024

Syphilis cases have been on the rise for more than a decade. New diagnoses have increased about 80 percent since 2018, a level not seen in the United States since 1950.

Cases are also on the rise in newborns. Congenital syphilis happens when an infected mother passes the disease to her baby during pregnancy. More than 3,700 cases of congenital syphilis were documented among newborns in 2022, about 10 times as many cases compared to 2012.

“We have seen a steady climb,” says Angelina Gangestad, MD, University Hospitals Division Chief of Obstetrics and Gynecology. “Initially, this rise was seen mainly in men who had sex with men, but now we’re seeing the rise in the heterosexual population and in newborns.”

What is Syphilis?

Syphilis is a sexually transmitted infection (STI) caused by the Treponema pallidum bacterium. It can be transmitted by vaginal, anal or oral sex. It can also be transmitted to a baby during childbirth.

Symptoms develop in stages, starting with a painless sore or lesion, usually around the penis, vagina, anus or mouth. Later, skin rashes appear in one or more places, along with other possible symptoms, including headaches, fever, swollen lymph glands, muscle aches, sore throat and weight loss.

Untreated syphilis can eventually lead to cardiovascular and neurological diseases and affect other organs.

Why are Cases Rising?

“We don’t have all the answers as to why it’s happening,” says. Dr. Gangestad. “There is speculation that it’s related to a decrease in condom use, which is related to lessening of the perceived threat from HIV. Because we’ve gotten better at treating HIV, people are decreasing condom use.”

Other possible factors:

Routine health screenings fell off during the pandemic and have not fully returned to pre-pandemic levels.
Access to contraception and sexual health services has become more challenging due to funding cuts.

“Access to services has been threatened the last few years, especially for women,” Dr. Gangestad says. “With legal issues around abortion care, many of the same places that provide abortion care also do STI testing.”

Detecting Syphilis

A simple blood test will detect syphilis. But initial symptoms are subtle and may be overlooked. “We pick up a significant amount of cases through prenatal screening and routine screening. It’s not patients walking in the door with symptoms,” says Dr. Gangestad.

Screening is done routinely for pregnant women. Maternal syphilis increases risk of premature birth and stillborn birth. An infection passed on to baby can lead to serious health problems for the baby and even death.

Those at highest risk for syphilis include:

Men who have sex with men.
People with multiple sex partners or who have sex with someone with multiple partners.
People who have unprotected sex.

Syphilis also is associated with increased risk of HIV.

Dr. Gangestad recommends people at elevated risk talk to their healthcare provider about being tested. Conversations about STD risk often don’t happen in primary care, but they should, she says.

How to Prevent Syphilis

Use a condom during sex.
Reduce the number of sex partners.
Avoid or limit drug and alcohol use before sex.
Ask sexual partners about their sex history and whether they’ve been tested for STDs.

Syphilis is treated with antibiotics. It’s possible to be infected again after treatment.