The number of syphilis patients in Japan has risen to 6,096, this year, a 47-year-high, the Tokyo-based National Institute of Infectious Diseases reported on Wednesday.
The latest figures as of Nov. 18 have already surpassed 2017’s 5,820 cases, with the numbers climbing especially among men in their 20s to 40s and women in their 20s, according to the Ministry of Health, Labour and Welfare.
The number of syphilis cases has increased dramatically since 2011, when the nation saw 827 cases, according to the ministry.
However, the cause of the rapid rise remains unclear.
About a quarter of the 6,096 cases or 1,548 were found in Tokyo this year, followed by 1,043 cases in the prefecture of Osaka, the institute said.
Of the 5,081 patients in the January-to-September period, men accounted for 66 per cent and women 34 per cent, according to the institute.
The ministry urged people to use condoms to prevent the disease or get tested immediately if they feel they might be infected.
Syphilis is a sexually transmitted disease (STD) caused by a bacterium it can cause serious health problems if not adequately treated.