Infectious syphilis outbreak in British Columbia: A changing epidemic
Although BC has been experiencing an outbreak of infectious syphilis (IS; primary, secondary, and early latent syphilis) since 1997, there have been recent important changes in the epidemic. Prior to 2003, British Columbia was unique worldwide because the outbreak was focused primarily in the Downtown Eastside heterosexual population[1] while elsewhere, the epidemic was based in men who have sex with men (MSM). Here, prior to 2003, fewer than 5% of individuals with infectious syphilis identified themselves as MSM. However, since January 2003, the epidemic in British Columbia has shifted, and now 50% of cases of new syphilis occur in MSM.[2] The majority of cases of IS in MSM have occurred in Vancouver and the Fraser Valley. The rising rates of syphilis are likely due to a variety of factors, including rising rates of unprotected anal intercourse and unprotected oral sex within the MSM population.[3] Approximately 15% of new cases of syphilis in MSM list unprotected oral sex as their only mode of contact, and in contrast to HIV, syphilis is quite effectively spread by fellatio. In addition, increasing use of street drugs such as crystal methamphetamine and crack/cocaine can influence sexual practices, with intoxicated individuals engaging in riskier sexual behaviors. As a result of rising rates of unprotected anal intercourse, BC’s gay community is also experiencing rising rates of HIV, hepatitis, and gonorrhea.
In an effort to address this shift in the syphilis epidemic to the MSM population, numerous interventions have been undertaken. Information regarding the syphilis outbreak is being widely distributed to clinicians who work with the MSM population through physician newsletters, rounds, and academic detailing by outreach nurses and physicians.[4] Outreach nurses are offering syphilis testing at community-based agencies for MSM and on the streets of the Downtown Eastside to improve access to both testing and treatment.[5] Community-based programs to enhance condom use in the MSM population, such as safer sex negotiating workshops, are being conducted by local community agencies.[6] Social networking, an innovative surveillance method, is being employed to better track and follow up cases and contacts and to improve mapping of the disease.[7,8] Community forums and messaging aimed at the MSM population continues to be offered. Education sessions are offered and delivered regularly by outreach nurses. Ads in local gay media describing the outbreak and the need to get tested begun in January 2003 have continued, and in late summer of 2004, a larger, province-wide media campaign is planned to ensure widespread awareness in the community.[9,10]
Clinical practice
This shift in the epidemic creates new issues for practising physicians. All individuals who attend for testing and evaluation for sexually transmitted infections should receive a syphilis test in addition to testing for other sexually transmitted infections. Men who have sex with men should be counseled regarding safer sex practices and informed about the syphilis outbreak and rising rates of sexually transmitted infections and HIV in the community. They should also be informed about the risks associated with syphilis acquisition with unprotected oral sex. Patients should also be informed that the use of street drugs and alcohol can lead to riskier sexual behaviors. Testing for syphilis and other sexually transmitted infections should be offered to those who have participated in unsafe sexual practices or who perceive themselves to be at risk. Physicians who work with HIV-positive MSM are also encouraged to offer screening to these patients on a regular basis. Clinicians should request a rapid plasma reagin test (RPR) and should send slides from any suspicious genital lesions for darkfield microscopy.
The current treatment of choice for early infectious syphilis remains penicillin G benzathine (trade name Bicillin) 2.4 million units i.m.[11] Doxycycline 100 mg p.o. b.i.d. for 14 days is an alternate in penicillin-allergic patients. Azithromycin 2 gm p.o. stat. can be used in special instances, but there are recent reports of treatment failures with this medication. All of these drugs are supplied free of charge by STD/AIDS control at the BC Centre for Disease Control.
—G.S. Ogilvie, MD, CCFP
—H.D. Jones, MD
—R. Marchand, PhD
—T. Trussler, EdD
—M.L. Rekart, MD, FRCPC
BC Centre for Disease Control
References
1. Patrick DM, Rekart ML, Jolly A, et al. Heterosexual outbreak of infectious syphilis: Epidemiological and ethnographic analysis and implications for control. Sex Transm Infect 2002;78(suppl 1):i164-i169. PubMed Abstract Full Text
2. Division of STD/AIDS Control. Division of STD/AIDS Control Annual Report. 2002. Vancouver: BC Centre for Disease Control, 2002. Full Text
3. Trussler T, Marchand R, Barker A. Sex Now by the Numbers: A statistical guide to health planning for gay men. Vancouver: Community Based Research Centre, 2003.
4. Thomson O’Brien MA, Oxman AD, Davis DA, et al. Educational outreach visits: Effects on professional practice and health care outcomes (Cochrane Review). In: The Cochrane Library, 2004;2. Chichester, UK: John Wiley & Sons, Ltd. www.cochrane.org/cochrane/revabstr/AB000409.htm [abstract] (accessed 29 March 2004).
5. Steiner KC, Davila V, Kent CK, et al. Field delivered therapy increases treatment for chlamydia and gonorrhea. Am J Public Health 2003;93:882-884. PubMed Abstract Full Text
6. Johnson WA, Hedges LV, Ramirez G, et al. HIV prevention research for men who have sex with men: A systematic review and meta-analysis. J AIDS 2002;30:S118-S129. PubMed Abstract Full Text
7. Rothenberg R, Kimbrough L, Lewis-Hardy R, et al. Social network methods for endemic foci of syphilis: A pilot project [comment]. Sex Transm Dis 2000;27:12-8. PubMed Abstract Full Text
8. Rothenberg RB, Sterk C, Toomey KE, et al. Using social network and ethnographic tools to evaluate syphilis transmission. Sex Transm Dis 1998;25:154-160. PubMed Abstract Full Text
9. Nicoll A. Assessing the impact of national anti-HIV sexual health campaigns: Trends in the transmission of HIV and other sexually transmitted infections in England. Sex Transm Infect 2001;77:242-247. PubMed Abstract Full Text
10. Agha S. The impact of a mass media campaign on personal risk perception, perceived self efficacy and on other behavioural predictors. AIDS Care 2003;15:749-762. PubMed Abstract
11. Division of STD Prevention and Control. Bureau of HIV/AIDS, STD and TB. Canadian STD Guidelines. Ottawa, ON: Health Canada, 1998. Document Highlights Full Text