Syphilis Cases in Japan Hit Record High for Fourth Consecutive Year in 2024
Syphilis infections in Japan have been rising rapidly in recent years, with cases expected to reach another record high in 2024 for the fourth straight year. Key factors include increased casual sex facilitated by dating apps, economic pressures forcing sex workers into riskier practices, and transmission expanding from men who have sex with men to the broader heterosexual population, including pregnant women.
I. Syphilis Resurging in Japan
- Japan has seen syphilis cases hit record highs each year from 2021-2023
- In Tokyo, syphilis infections reached 2,460 by early September 2024, approaching the all-time high of 3,701 in 2023
- Nationwide, over 15,000 cases were reported in 2023, a 12-fold increase from a decade ago
II. Social and Economic Factors Fueling Spread
- Sluggish economy and widening income inequality driving many, especially young women, into high-risk sex work
- COVID-19 caused over 300,000 sex industry workers to lose jobs, pushing some into unregulated street prostitution
- Proliferation of dating apps enabling random, unprotected encounters that can efficiently spread infection
III. Transmission Expanding from MSM to Broader Population
- Syphilis outbreaks previously concentrated among men who have sex with men (MSM)
- Now rapidly increasing among heterosexual men and women in Japan and globally
- Serious concern about congenital syphilis cases from pregnant women infecting babies
IV. Public Health Implications
- Syphilis has severe health impacts including damage to brain, heart and other organs if untreated
- Places major burden on healthcare systems, with WHO estimating 7 million new syphilis cases globally per year
- Screening and early treatment critical, but messaging around prevention is complicated
The resurgence of syphilis in Japan reflects a complex intersection of social, economic and behavioral factors that are enabling rapid disease transmission. Addressing this crisis will require increased screening and treatment, but also frank public discussion about the underlying issues fueling the epidemic. As transmission expands into the general heterosexual population, the stakes could not be higher in terms of controlling the outbreak. Health authorities in Japan and worldwide must act decisively to combat this serious threat to public health.