TABLE 2—
Internet and Methamphetamine Use Among Interviewed Primary and Secondary Syphilis Patients Who Were Men Who Have Sex With Men (MSM), by Region: California, 2004–2008
| Regiona | MSM With Syphilis, No. (%) | Syphilis Rateb per 100 000 | Internet Use, No. (%) | Methamphetamine Use, No. (%) | No. of Sex Partners,c Mean (95% CI) |
| Northern | 176 (3.0) | 33.5 | 46 (26.1) | 18 (10.2) | 4.9 (2.7, 7.0) |
| Bay Area | 545 (9.6) | 68.9 | 214 (37.9) | 107 (18.9) | 5.5 (4.7, 6.3) |
| San Francisco | 1046 (17.7) | 331.6 | 465 (44.5) | 278 (26.6) | 10.1 (9.1, 11.1) |
| Central | 82 (1.4) | 19.2 | 34 (41.5) | 15 (18.3) | 3.9 (2.8, 4.9) |
| Southern | 2002 (33.8) | 116.0 | 800 (40.0) | 467 (23.3) | 6.0 (5.5, 6.6) |
| Los Angeles | 2045 (34.6) | 164.6 | 589 (28.8) | 253 (12.4) | 6.5 (5.8, 7.1) |
Note. CI = confidence interval. Cases with outlier partner data (≥ 200 partners) are excluded. “Internet use” means use of Internet to meet sex partners.
Jurisdictions were as follows: Northern region: Alpine, Amador, Butte, Calaveras, Colusa, Del Norte, El Dorado, Glenn, Humboldt, Lake, Lassen, Mendocino, Modoc, Nevada, Placer, Plumas, Sacramento, San Joaquin, Shasta, Sierra, Siskiyou, Sutter, Tehama, Trinity, Yolo, and Yuba; Bay Area region: Alameda, Berkeley, Contra Costa, Marin, Napa, San Mateo, Santa Clara, Solano, and Sonoma; Central region: Fresno, Inyo, Kings, Madera, Mariposa, Merced, Mono, Monterey, San Benito, Santa Cruz, Stanislaus, Tuolumne, and Tulare; Southern region: Imperial, Kern, Long Beach, Orange, Pasadena, Riverside, San Bernardino, San Diego, San Luis Obispo, Santa Barbara, and Ventura.
We calculated the San Francisco rate using a 15.4% estimate of male population for the MSM population denominator. For all other regions, we used a 5.2% estimate of male population.
Sex partner statistics exclude cases with missing partner data.