Syphilis is surging: Who is affected and how do we respond?

What is syphilis?

Syphilis is a complex, multistaged disease caused by Treponema pallidum, a treatable bacterial infection once thought to be close to eradication. Syphilis is spread through sexual contact or can be transmitted to the fetus during pregnancy.¹

During the infection's early stages, people can experience symptoms including genital lesions or rashes, but the infection is asymptomatic.² Because of this, infected individuals often do not realize they have been exposed and the infection is unknowingly spread to sexual partners, or for pregnant women to their unborn child.¹ In adults, untreated infection can eventually lead to organ failure, neurodegenerative disease and eventually death.¹ In pregnant women, the bacteria can cross the placenta and infect the fetus, leading to fetal death, preterm birth, and significant developmental sequalae in the infant.³

Who is most affected by increasing rates of syphilis in the US?

Unfortunately, the rates of syphilis diagnosis increased by almost 80% between 2018 and 2022 in the US, according to the Centers for Disease Control (CDC).⁴ Approximately 45% of all reported cases of syphilis in the US between 2018-2022 were among men who have sex with men (MSM), increasing by 6.6% over the 4-year span.⁵ Strikingly, syphilis among women increased 193% during the same time period.⁶ This concerning rise in diagnoses was also closely associated with a concurrent increase in congenital syphilis, which increased from 1325 cases in 2018 to 3755 cases in 2022.⁵ While the condition is still the most prevalent in MSM, there has been a sharp increase in diagnosis among women of reproductive age.⁶ Because of the prevalence among both groups, they must be centered more in interventions that can help improve these current trends.^7,8

Syphilis also has disproportionate effects on people of different races/ethnicities and on those of lower socioeconomic status.⁵ Native Americans and African Americans are the two most disproportionately affected groups with the condition, having a rate of 67 per 100,000 people and 40 per 100,000 in 2022, respectively. ^9,10  These rates are considerably higher than those of White and Asian Americans, who have rates under 10 per 100,000 people. When considering congenital syphilis, Native Americans also had the highest rate at 644 per 100,000, which was even three times greater than that of African Americans at 215 per 100,000.¹¹

These disparities in diagnosis are influenced by factors including lack of access to healthcare in rural communities, fear/mistrust of healthcare providers, concerns about cost of healthcare, and lack of education regarding the importance of prevention, diagnosis, and treatment of STIs, especially during pregnancy.^7,12 These numbers clearly illustrate the need for health equity in primary and reproductive healthcare for underserved communities. By utilizing this data, providers and others working in healthcare can begin to craft a useful roadmap for prioritization of resources in our efforts to reverse the surge in syphilis rates.

Then and now, how are we responding to surging rates of syphilis in the US?

In the 1990s, syphilis was close to eradication due to 2 valuable assets: (1) the availability of cheap yet accessible treatment and (2) the considerable number of highly visible campaigns seeking to educate the public about STIs during the HIV/AIDS epidemic.^13,14 But between then and now, we have seen a considerable shift in both.^15,16

If we want to repeat the successes of the past with syphilis, we should undertake a similar coordinated response. The response would include input on a federal, state, and community level, with programs and initiatives supporting STI prevention, education, and treatment across all affected communities.

To date, the response to the ongoing increase in syphilis cases in the US has been slow. But we are seeing some progress through the following government and community programs:

• Federal level: In January of this year, the US Department of Health and Human Services established the National Syphilis and Congenital Syphilis Syndemic (NSCSS) Federal Task Force with the goal of slowing the spread of syphilis through targeted support of affected communities.¹⁷ While there is currently no federal guidance, the CDC proposed guidelines supporting doxy-PEP in October 2023, and final publication of these recommendations are expected in the near future.¹⁸
• State level: The Illinois Department of Public Health launched the Perinatal Syphilis Warmline in November 2023, to help support the medical community of that state in its response to increasing syphilis infections. The phone line, mirrored after a similar hotline developed for the response to HIV, serves as an informational triage that can provide individualized guidance on the interpretation of syphilis test results and treatment strategies.¹ Another state-and city-level initiative has been the incorporation of recommendations for the use of doxycycline post-exposure prophylaxis (doxy-PEP), which is a prophylactic strategy shown to reduce syphilis transmission by 77% in the high-risk MSM population.²⁰ In August 2023, the Michigan Department of Health and Human Services indicated support of the use of doxy-PEP in MSM and transgender women with a history of STI.²¹
• City level: The New York City Department of Health initiated guidance for the use of doxy-PEP in November 2023,²¹ while the San Francisco Department of Public Health incorporated these recommendations in 2022 and have recently reported a 50% decrease in STIs.²²

In summary, while this is just a small sample of initiatives, they are good examples of the different strategies being leveraged to combat the increasing rates of syphilis in the US.

Where does Quest Diagnostics fit into syphilis testing and prevention?

Echoing Admiral Rachel Levine’s words from the Department of Health and Human Services’ strategy to slow the spread of syphilis, this must be “a concerted effort.”¹⁷ Quest Diagnostics has put forth initiatives to provide comprehensive screening for not only syphilis but for many other sexually transmitted infections. Within those efforts, providers also have access to 600+ medical experts with MDs, PhDs, and DOs, who can help with test selection and result interpretation.

To learn more about what Quest Diagnostics Women’s Health has to offer for STI testing, please visit https://www.questwomenshealth.com/symptomatic-visit/female-testing.

References

1. Centers for Disease Control and Prevention (CDC). Syphilis – CDC basic fact sheet. Page last reviewed February 10, 2022. Accessed April 1, 2024. https://www.cdc.gov/std/syphilis/stdfact-syphilis.htm
2. Tudor ME, Al Aboud AM, Leslie SW, et al. Syphilis.[Update May 20, 2023]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024. Available from: https://www.ncbi.nlm.nih.gov/books/NBK534780/
3. World Health Organization (WHO). Mother-to-child transmission of syphilis. Accessed April 2, 2024. https://www.who.int/teams/global-hiv-hepatitis-and-stis-programmes/stis/prevention/mother-to-child-transmission-of-syphilis
4. CDC. Table 35. Trends in reported cases and rates of reported cases for nationally notifiable STIs, United States, 2018–2022. Accessed April 2, 2024.  https://www.cdc.gov/std/statistics/2022/tables/35.htm
5. CDC. National overview of STIs, 2022. Sexually Transmitted Infections Surveillance, 2022. Accessed April 2, 2024. https://www.cdc.gov/std/statistics/2022/overview.htm
6. CDC. Table 24. Primary and secondary syphilis among women — reported cases and rates of reported cases by state/territory and region in alphabetical order, United States, 2018–2022. Sexually Transmitted Infections Surveillance, 2022. Accessed April 2, 2024. https://www.cdc.gov/std/statistics/2022/tables/24.htm
7. Stahlman S, Plant A, Javanbakht M, et al. Acceptable interventions to reduce syphilis transmission among high-risk men who have sex with men in Los Angeles. Am J Public Health. 2015;105(3):e88-e94. doi:10.2105/AJPH.2014.302412
8. Stone W. Syphilis among newborns continues to rise. Pregnant moms need treatment, CDC says. NPR Shots. November 7, 2023. Accessed April 2, 2024.  https://www.npr.org/sections/health-shots/2023/11/07/1211172725/syphilis-among-newborns-continues-to-rise-pregnant-moms-need-treatment-cdc-says
9. CDC. Primary and secondary syphilis – rates of reported cases by race/Hispanic ethnicity, US, 2018 – 2022. Accessed April 2, 2024. https://www.cdc.gov/std/statistics/2022/figures/syph-1.htm
10. Nowell C. Native Americans are hardest hit by syphilis surge. NPR Shots. March 21, 2024. Accessed April 1, 2024.  https://www.npr.org/sections/health-shots/2024/03/21/1239772654/native-americans-are-hardest-hit-by-syphilis-surge
11. CDC. Table 33. Congenital syphilis — reported cases and rates of reported cases* by year of birth and race/Hispanic ethnicity of mother, united states, 2018–2022. Accessed April 2, 2024. https://www.cdc.gov/std/statistics/2022/tables/33.htm
12. Amerson EH, Castillo Valladares HB, Leslie KS. Resurgence of Syphilis in the US—USPSTF Reaffirms Screening Guidelines. JAMA Dermatol. 2022;158(11):1241–1243. doi:10.1001/jamadermatol.2022.3499
13. Valentine JA, Bolan GA. Syphilis Elimination: Lessons Learned Again. Sex Transm Dis. 2018;45(9S Suppl 1): S80-S85. doi:10.1097/OLQ.0000000000000842
14. ho KK. US syphilis numbers are at their highest since the 1950s, CDC report says. The Washington Post. February 1, 2024. Accessed April 1, 2024. https://www.washingtonpost.com/health/2024/02/01/syphilis-cases-surge-united-states/
15. Kirzinger A, et al. Public knowledge and attitudes about sexually transmitted infections: KFF polling and policy insights. KFF. Published February 18, 2020. Accessed April 2, 2024. https://www.kff.org/womens-health-policy/issue-brief/public-knowledge-and-attitudes-about-sexually-transmitted-infections/
16. Hunter K. Syphilis and other STDs are on the rise. States lost millions of dollars to fight and treat them. Associated Press. October 28, 2023. Accessed April 2, 2024. https://apnews.com/article/syphilis-std-cdc-federal-funding-e82f78f3d30c393538e5e421548e7758
17. HHS announces department actions to slow surging syphilis epidemic. US Department of Health and Human Services. January 30, 2024. Accessed April 2, 2024. https://www.hhs.gov/about/news/2024/01/30/hhs-announces-department-actions-slow-surgng-syphilis-epidemic.html
18. CDC. Public Comment Period for Doxy PEP Guidelines. October 2, 2023. Accessed April 2, 2024. https://www.cdc.gov/std/dstdp/dcl/2023-october-2-doxy-pep-guidelines.htm
19. IDPH launches new provider phone line in response to alarming increase in babies born with congenital syphilis. Illinois Department of Public Health (IDPH). November 2, 2023. Accessed April 2, 2024. https://dph.illinois.gov/resource-center/news/2023/november/2023-11-02---idph-launches-new-provider-phone-line-in-response-t.html
20. Luetkemeyer AF, Donnell D, Dombrowski JC, et al. Postexposure doxycycline to prevent bacterial sexually transmitted infections. N Engl J Med. 2023;388(14):1296-1306. doi:10.1056/NEJMoa2211934
21. Michigan Department of Health and Human Services. STI information for providers, local health departments and other organizations. Accessed April 2, 2024. https://www.michigan.gov/mdhhs/keep-mi-healthy/chronicdiseases/hivsti/resources/sexually-transmitted-infections
22. Doxycycline post-exposure prophylaxis (doxy-pep) to prevent bacterial sexually transmitted infections. New York City Department of Health and Mental Hygiene. November 9, 2023. Accessed April 2, 2024. https://www.nyc.gov/assets/doh/downloads/pdf/std/dear-colleague-doxy-PEP-to-prevent-bacterial-STI-11092023.pd
23. Sexual health prevention tool associated with declines in sexually transmitted infections in San Francisco. SF.gov. March 4, 2024. Accessed April 2, 2024. https://www.sf.gov/news/sexual-health-prevention-tool-associated-declines-sexually-transmitted-infections-san