August 26, 20244 min readAt-Home Syphilis Test Could Increase Access and Combat EpidemicAn easy-to-access rapid test could lower barriers to detecting syphilis, which is surging nationwideBy Saima S. IqbalIllustration, Treponema pallidum bacteria which causes syphilis. Robert Brook/Science Photo Library/Getty ImagesOn August 16 the U.S. Food and Drug Administration authorized the sale of the first over-the-counter at-home test for syphilis in an effort to contain a national surge in the sexually transmitted infection (STI).The new test, which turns around results within 15 minutes, takes finger pricks of blood and scans them for immune molecules called antibodies that bind to the bacterium that causes syphilis. A positive finding warrants a follow-up with a health care provider who can confirm ongoing infection and provide effective antibiotic treatment. Manufacturer NOWDiagnostics says the product is expected to reach pharmacies and retail stores later this year.Other kinds of rapid syphilis tests can only be administered by medical professionals or certain community organizations. Yet stigma often prevents people and the providers who work with them from bringing up sexual health concerns. Like an at-home test for gonorrhea and chlamydia that was approved late last year, the new syphilis assay offers people the privacy to test themselves in their own home.On supporting science journalismIf you’re enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.“This is a real breakthrough,” says Jeffrey Klausner, former director of the San Francisco Department of Public Health’s STD Prevention and Control Services and an epidemiologist at the Keck School of Medicine of the University of Southern California.Cases of the majority of STIs most notably syphilis, have mushroomed in the U.S. over the past decade. From 2018 to 2022 alone, the number of syphilis cases in the U.S. increased by nearly 80 percent, surpassing 207,000—a 70-year high. The disease is increasingly common in pregnant people, who can also transmit the infection to their fetuses in utero through the bloodstream or during vaginal birth. In 2022 syphilis appeared in 280 out of every 100,000 people who gave birth and 3,700 babies were born with the disease, according to the Centers for Disease Control and Prevention.A subset of people with untreated infections incur serious damage to their heart, brain or other major organs. When passed along during pregnancy, syphilis often causes miscarriage or infant death.Public health experts say soaring infection rates reflect widespread difficulties in accessing health care. “Syphilis is like the canary in the coal mine,” explains Barbara Van Der Pol, an epidemiologist at the University of Alabama at Birmingham. “When our public health infrastructure starts to fail, syphilis always increases.”Funding for sexual health clinics in the U.S., when adjusted for inflation, has dropped over the past two decades. As a result, many groups that raise awareness of and help screen for STIs have closed their operations, Van Der Pol and Klausner say.To the untrained eye, syphilis can be hard to detect. Immediately after infection, people often develop genital sores and, several weeks later, body-wide rashes and fever. But the sores tend to be painless and can hide inside the vagina or anus. And doctors can mistake syphilis’s second wave of symptoms for those of common viral infections. After a year the bacteria go dormant in the body, but people remain somewhat contagious and can sporadically develop severe health complications. Some otherwise healthy adults now run into these complications weeks or months after infection, according to Arlene Seña-Soberano, a public health researcher at the University of North Carolina at Chapel Hill.Individuals at high risk of infection include people who have unprotected sex or have multiple sex partners, men who have sex with men, people with HIV and other immunosuppressive conditions and people who use injectable drugs. The CDC also recommends that all sexually active people aged 15 to 44 be offered annual screening for the infection, regardless of their individual sexual habits, in areas with a greater than 0.0046 percent incidence of syphilis among women in that age group. All pregnant people are encouraged to undergo testing at their first prenatal visit.To more effectively stop the spread, the U.S. needs to develop a culture of regular STI testing, Van Der Pol says. “If we get to the point where people test annually at least or whenever they have concerns in the back of their mind—if we make [testing] a really normal activity—then we’re going to start to be impactful,” she adds.As Klausner sees it, stigma also prevents communities from mobilizing to spur further governmental action. “The reality of living in a democracy is that resources go to those who scream the loudest,” he says. Earlier this year the Department of Health and Human Services established a national task force to respond to the syphilis epidemic. Klausner imagines activists could pressure the federal government to make rapid tests like the recently approved one available for free via local health departments and community organizations.With an estimated sticker price of $29.98, the new test might not benefit some of the most vulnerable populations, such as people who are unhoused or those with substance use disorders. Sexual health advocates might also encourage the government to manufacture penicillin. Global supply chain disruptions caused a shortage of the frontline treatment that began in June 2023 and only partially eased months ago. (An alternate treatment exists, but it is more cumbersome to use and is not safe for pregnant people.)“When I was the public health director in San Francisco, it was very clear that when we had political will and adequate resources, we could bring these types of infections under control,” Klausner says.