How Much Do Young Australians Know About Syphilis Compared With Chlamydia and Gonorrhea? Findings From an Online...

There is increased heterosexual transmission of syphilis in Australia, an infection with severe outcomes. Australian policy emphasizes increasing sexually transmissible infection knowledge/awareness. However, little is known about young Australians' perceptions and knowledge of syphilis.

Our online sexual health survey was open May 2 to June 21, 2022, to 16- to 29-year-olds in Australia. We asked participants if they were aware of syphilis, their personal risk perception, and perceived severity of infection and compared with results for chlamydia/gonorrhea. Multivariable and multinomial logistic regressions were used to assess characteristics associated with outcomes. We measured sexually transmissible infection knowledge using 10 true/false statements (5 syphilis, 5 chlamydia/gonorrhea).

Among 2018 participants (69.1% women, 48.9% heterosexual), 91.3% had heard of syphilis (vs. 97.2% for chlamydia and 93.3% for gonorrhea). Older (25-29 years; adjusted odds ratio [aOR], 2.4; 95% confidence interval [CI], 1.4-4.4) and gay/lesbian (aOR, 2.8; 95% CI, 1.4-5.3) respondents were more likely to have heard of syphilis, as were those who were non-Aboriginal, sexually active, and with a school-based sex education. Syphilis knowledge was lower than chlamydia/gonorrhea knowledge ( P < 0.001). More than half (59.7%) perceived syphilis to have serious health impacts (vs. 36.4% for chlamydia and 42.3% for gonorrhea). Older respondents were more likely (25-29 years; aOR 2.1; 95% CI, 1.6-2.8), and gay/lesbian respondents less likely (aOR, 0.7; 95% CI, 0.6-1.0) to perceive syphilis to have serious health impacts. One-fifth of sexually active participants were unsure of their risk of syphilis.

Most young Australians are aware of syphilis, but few have comprehensive knowledge about the infection relative to chlamydia/gonorrhea. Considering increasing heterosexual transmission, syphilis health promotion campaigns should expand their focus.