The Internet: An Emerging Venue for Syphilis Epidemics Among Men Who Have Sex with Men in Los Angeles LAC - DHS Getahun Aynalem, MD, MPH, Kellie Hawkins, MPH Lisa V. Smith, MS, Dr. PH, Cathleen Bemis, MS, Melanie Taylor, MD, MPH, Peter Kerndt, MD, MPH Los Angeles County Department Health Services STD Program
Introduction Since the last quarter of 2000, there has been an outbreak of syphilis primarily affecting MSM in Los Angeles. Traditionally, popular sex venues for the MSM population have been bathhouses, bars/clubs, streets, motels, and parks and the use of these venues to meet sexual partners. Recently, the use of the Internet among MSM in California is emerging as a dominant venue for meeting sexual partners. Although it has been shown that popular sex venues have been associated with drug use, unprotected anal intercourse and anonymous sex, little is known about: –the impact of Internet on the incidence of STDs, including HIV and syphilis. –the difference between MSM with syphilis who use the Internet for sexual encounter and those who do not. LAC - DHS
Introduction * Does not include cases lacking partner information Source: LAC-DHS, Early Syphilis Surveillance Summary – as of December 31, 2003 LAC - DHS 1 1
Early Syphilis Cases By HIV Serostatus & Sexual Orientation, 2001–2003 (n=1,465) Source: LAC-DHS, Early Syphilis Surveillance Summary – as of December 31, 2003 Sexual Orientation LAC - DHS
Objectives To identify the demographic and behavioral characteristics of MSM diagnosed with syphilis that reported using the Internet for sexual encounter during the “Critical period” for syphilis infection. To assess the difference in risk behaviors between those who use the Internet for sexual encounters and those who do not. To identify the most common Internet sites for sexual encounters used by MSM with early syphilis diagnosis. LAC - DHS Critical period: Primary syphilis - 90 days, Secondary syphilis months preceding the onset of symptoms; and Early latent – one year prior the date of treatment.
Methods Between January 2001 and December 2003, demographic, behavioral and venue information were collected from 899 MSM who were diagnosed with early syphilis (primary, secondary and early latent). Association between demographic and behavioral characteristics with Internet use for sexual encounter were assessed using chi-square and Fisher’s exact test. Independent predictors of Internet use and the odds of initiating sexual contact through the internet were calculated using logistic regression. The most frequent internet sites for initiating sexual encounter reported by MSM with syphilis diagnosis were also documented. LAC - DHS
Results Demographic, behavioral, and venue information were collected for 899 MSM early syphilis cases during field interviews. Of these, 205 (22%) met sex partners via the Internet. –65% were HIV positive by self-report. LAC - DHS
Trends in Internet Use for Sexual Encounters by MSM with Syphilis Diagnosis, LAC - DHS
Internet Use for Sexual Encounters Among MSM with Syphilis Diagnosis, By Age Demographic CharacteristicsTotal Used the Internet for Sexual encounter Yes N (%) No N (%) P - value Overall (22.8)694 (77.2) Age (y) 0.66 < (1.0) 11 (1.6) (19.0) 129 (18.6) (45.9) 284 (40.9) (23.4) 190 (27.4) 50 + Median age (10.7) (11.5) 36 _____________________________________________________________________________________________ ** p-value < 0.05 LAC - DHS
Internet Use for Sexual Encounters Among MSM with Early Syphilis, By Race/Ethnicity and HIV Status Demographic Characteristics Total Used the Internet for Sexual Encounter Yes N (%) No N (%) P - value Overall (22.8)694 (77.2) Race/ethnicity0.01* White (67.3) 293 (42.2) African American (6.8) 80 (11.5) Hispanic (19.5) 283 (40.8) Other/Mixed (6.3) 38 (5.5) HIV Status0.43 Positive (65.3) 403 (62.2) Negative (34.7) 245 (37.8) * p-value < 0.05 LAC - DHS
Risk Behaviors Among MSM with Early Syphilis, By Internet Use for Sexual Encounters Risk Behaviors Total Used the Internet for Sexual Encounter Yes N (%) No N (%) P - value Anal insertive Sex0.01* Yes (90.9) 538 (80.1) No (9.1) 134 (19.9) Anal receptive Sex0.10 Yes (84.2) 524 (78.9) No (15.8) 140 (21.1) Oral sex0.01* Yes (99.5) 632 (93.9) No 42 1 (0.5) 41 (6.1) Anonymous partner0.01 * Yes (91.1) 501 (74.9) No (8.9) 169 (25.2) * p-value < 0.05 LAC - DHS
Risk Behaviors Among MSM with Early Syphilis, By Internet Use for Sexual Encounters Used the Internet for Sexual Encounter Risk Behaviors TotalYes N (%)No N (%)P - value Condom used0.60 Yes25262 (33.7)190 (31.7) No (66.3)410 (68.3) Incarcerated past year 0.13 Yes324 (2.2)28 (4.7) No (97.8)564 (95.3) IV drug user0.02* Yes188 (4.1)10 (1.5) No (95.9)664 (98.5) Non-IV drug user0.01* Yes25273 (38.2)179 (26.6) No (61.8)494 (73.4) *p-value<0.05 LAC - DHS
Drug Use Among MSM with Early Syphilis, By Internet Use for Sexual Encounters LAC - DHS *GHB: Gamma hydroxy butyrate
Influence of Sociodemographics on Internet Use for Sexual Encounters Among MSM with Syphilis Diagnosis Variables Odds ratio (95% CI) Univariate analysis Multivariate analysis Demographic Age (y) > 30 vs. < (0.9 – 1.1)1.8 (0.9 –3.4) Race/ethnicity White vs. Non-white2.6 (1.2 – 3.8)*3.1 (1.8 – 5.3)* HIV Positive Yes vs. No1.0 (0.7 – 1.5)1.5 (0.9 –2.6) Behavioral Anal Inserive Yes vs. No2.0 (1.2 – 3.6)*1.5 (0.7 – 3.2) Anal receptive Yes vs. No1.4 (0.9 – 2.3)1.3 (0.6 – 3.2) Oral sex Yes vs. No10.1 (1.4 – 74.9)*2.4 (0.2 – 23.8) Anonymous Partners Yes vs. No3.8 (2.0 – 7.1)*2.4 (1.1 – 5.5) * Condom Use Yes vs. No0.9 (0.6 – 1.5)1.5 (0.8 – 2.6) Incarcerated Yes vs. No0.4 (0.1 – 1.2)0.3 (0.1 – 1.6) IV Drug User Yes vs. No2.6 (1.0 – 7.1)*3.0 (0.5 – 19.3) Non-IV drug User Yes vs. No1.7 (1.2 – 2.5)*1.6 (0.9 – 2.7) * p<0.05 LAC - DHS
Reported Internet Sites Used for Sexual Encounters by MSM with Syphilis in Los Angeles LAC - DHS
Conclusion Overall 22% MSM who were diagnosed with early syphilis infection met their sexual partners through the Internet –65% were HIV positive MSM with early syphilis who do use the Internet to meet their sexual partners were: –2.6 times more likely to be White –3.8 times more likely to have anonymous sex –2.6 times more likely to use injection drugs Independent predictors of meeting sexual partners via the Internet among MSM with early syphilis were: –White race –Having anonymous sex partners LAC - DHS
Recommendations Potential public health prevention and control efforts should include interventions like online outreach and automated behavioral risk reduction. The Internet is an important venue for conducting STD/HIV prevention and control. LAC - DHS
Future Directions Identify additional Internet sites used for sexual encounters among MSM early syphilis cases. Explore the association between socio- economics and the ethnicity of persons using the internet as a sex venue. LAC - DHS