Background:
Between 1999 and 2002, San Francisco experienced a sharp increase in early syphilis among gay and bisexual men. In response, in 2002, we launched a syphilis awareness social marketing campaign, Healthy Penis. The campaign was continued through 2005. A previous evaluation of the campaign was conducted in 2002-2003.

Objective:
To assess continued awareness and impact of the Healthy Penis campaign among the target population.

Method:
Between September 2004 and March 2005, we conducted interviewer-administered surveys of a convenience sample of gay and bisexual men in San Francisco. The surveys assessed recognition and impact of the Healthy Penis campaign, awareness of the syphilis epidemic, syphilis testing history, and knowledge of syphilis symptoms and modes of transmission. Statistical analyses included chi-square and nonparametric tests and logistic regression.

Result:
Eighty-four percent of the respondents (N= 151) were aware of the campaign (40% recalled the campaign spontaneously and 44% recalled the campaign when prompted). Respondents aware of the Healthy Penis campaign were more likely than those unaware to: have recent casual/anonymous sex partners, have heard of recent increases in syphilis; to know that HIV helps spread syphilis and vice versa; and to correctly respond to questions about syphilis symptoms and modes of transmission. In addition, respondents with casual/anonymous partners and those with campaign awareness were more likely to have had a recent syphilis test. After controlling for other factors, respondents with unaided awareness of the campaign were 3.1 (95% CI 1.8, 5.4) times more likely to have had a recent syphilis test.

Conclusion:
Our survey analysis found that the Healthy Penis campaign continued to sustain an effect, for at least two years, in increasing syphilis testing and knowledge and raising awareness about the syphilis epidemic among gay and bisexual men.

Implications:
Social marketing campaigns can be an effective tool for increasing awareness and encouraging behavior change.