Health officials are raising urgent concerns as syphilis infections surge across the United States, with several California counties reporting particularly alarming rates.
Public health leaders say the spike mirrors trends not seen in decades, prompting renewed calls for widespread testing — especially among sexually active individuals and pregnant women, KTLA5 reported.
Across the country, syphilis cases have risen sharply over the past decade. In states like New York, infections have increased fivefold since 2013, reflecting a broader nationwide trend.
Even more concerning, federal data shows congenital syphilis — when the infection is passed from a pregnant mother to her baby — has skyrocketed by 700% compared to roughly ten years ago.
Congenital cases can have devastating consequences, including miscarriage, stillbirth, infant death, or serious lifelong health complications such as organ damage and bone deformities.
Despite progress in reducing other sexually transmitted infections like chlamydia and gonorrhea, congenital syphilis has continued climbing year after year. By 2024, it marked 12 consecutive years of increases, reaching its highest level since 1994.
The Centers for Disease Control and Prevention (CDC) has set a national goal of reducing syphilis rates among women of reproductive age to 4.6 cases per 100,000 people by 2030.
To reach that benchmark, health officials are urging providers to routinely screen people between the ages of 15 and 44 in areas where infection rates are elevated.
Repeat testing is also recommended during pregnancy in the hardest-hit regions to prevent transmission to newborns.
Within California, infection rates vary widely — but several densely populated counties are reporting troubling numbers.
Fresno County leads the state with the highest rate among major counties, reporting 30.4 cases per 100,000 women ages 15 to 44. Sacramento County follows at 24.6, while Kern County reports 18.8.
Los Angeles County — the state’s most populous — recorded a rate of 12.9, slightly above San Francisco County at 12.7. Other counties including Alameda (11.1), San Bernardino (10.8), and Contra Costa (10.0) also exceeded federal targets.
San Diego (9.3), Riverside (8.1), Ventura (7.6), and Orange County (5.5) reported moderate rates, while Santa Clara County had the lowest among major regions at 3.9.
“For many people, the most significant risk factor for syphilis is living in a community with high rates of syphilis,” the CDC said.
Syphilis is a sexually transmitted infection caused by bacteria that can progress in stages if left untreated.
It spreads through direct contact with a syphilis sore during sex and can also be passed from a pregnant person to their baby.
Early symptoms often include painless sores that can go unnoticed. As it progresses, people may develop rashes, fever and other flu-like symptoms, before entering a stage where symptoms disappear despite the infection remaining in the body.
The disease has been documented for centuries, with major outbreaks dating back to Europe in the late 1400s, contributing to its reputation as a long-standing and serious public health threat.
Medical experts say the infection can be difficult to detect in its early stages.
The first signs typically appear within two to six weeks after exposure, according to Dr. Khalil Ghanem, a professor of medicine at Johns Hopkins Medicine. Early symptoms often include painless sores that can easily go unnoticed.
“Syphilis is kind of complicated,” Dr. Lazarus Gehring, medical director of the health department in Broome County, New York told KTLA. “There’s multiple stages and phases, and there’s asymptomatic ones, too.”
Although initial symptoms may disappear, the infection does not go away without treatment.
As it progresses, the disease can enter a secondary stage where bacteria spread throughout the body, potentially causing fever, rashes, and other systemic symptoms.
In some cases, symptoms fade again, leading to what is known as latent syphilis.
“Sixty percent of people with latent syphilis will never have symptoms again. The other 40% suffer devastating complications including neurological problems, cardiovascular issues, and inflammatory masses all over the body,” Dr. Ghanem told the network. “Overall, 10% of patients who are not treated for syphilis wind up dying from this infection. … Syphilis is a cruel disease.”
Health experts emphasize that early detection can make a crucial difference.
Syphilis can be effectively treated — and cured — with antibiotics such as penicillin, particularly when caught in its early stages.
With cases rising across California and beyond, officials are urging sexually active individuals to get tested regularly, even if they are not experiencing symptoms.
