In recent years, Japan’s seen a huge spike in syphilis cases. The latest numbers aren’t any better, with Tokyo reporting its fourth consecutive increase last year. There are now 7.4 times as many cases compared to 10 years ago.
In the 2000s, cases of the sexually transmitted disease in Japan were below 1,000 a year. Even in 2012, there were only 875 cases across Japan.
This started to rise, however, in the middle of the 2010s. As of 2023, there were 14,906 cases of syphilis nationwide – a full 15x increase over 15 years. Incidents have increased 10 times among men and 23 times among women. Cases of gonorrhea and chlamydia have also risen.
The latest numbers from Tokyo don’t show any sign of the contagion slowing down, either. Figures for 2024 from Tokyo say there were 3,748 cases across the metropolitan area. That’s an increase of 7.4 times over the past 10 years. It’s also the fourth year in a row that numbers have gone up.
Tokyo city officials say that the increase is likely due to the ease of meeting and hooking up with strangers. Some experts say another cause of the increase is people’s unwillingness to discuss STDs, combined with a general lack of knowledge or belief in erroneous information.
The increase is most marked in men between the ages of 20 and 50 and women in their 20s.
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Most in Japan tend to think of STDs as a problem for those who use or work in one of Japan’s many varieties of seifuzoku (性風俗) or sexual services, such as soaplands or delivery health hotel-based services. However, data shows that 30 percent of syphilis cases occur among people with no experience in Japan’s sex industry.
According to national data, the majority of cases occur in large cities like Tokyo and Osaka. However, prefectures across the country have seen spikes in infections as well. In Nagasaki, cases in 2021 rose 2.81 times to 146 people. Totori, Yamagata, and Wakayama Prefectures have also seen substantial increases.
While a treatable STD, syphilis can lead to severe complications if left untreated. Secondary syphilis can result in sores, hair loss, muscle aches, and other symptoms. Tertiary syphilis, which occurs in 30 to 40 percent of people who don’t seek treatment, can suffer damage to their brain, nerves, and other organs.
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