The findings and conclusions in these presentations have not been formally disseminated by the Centers for Disease Control and Prevention and should not be construed to represent any agency determination or policy.

Wednesday, May 10, 2006

Outbreak of Syphilis on and Bordering an American Indian Reservation

David Wong, Division of STD Prevention, CDC assignee to the Indian Health Service, 5300 Homestead Rd NE, Albuquerque, NM, USA, JV Iralu, Internal Medicine, Indian Health Service, 801 Thompson Avenue, Suite 400, Rockville, MD, USA, LK Shelby, Division of STD Prevention, CDC, 5300 Homestead Rd NE, Albuquerque, NM, USA, JE Cheek, Division of Epidemiology and Disease Prevention, Indian Health Service, 5300 Homestead Rd., NE, Albuquerque, NM, USA, C. Almeida, Department of Family Medicine, University of California at Irvine, Irvine, CA, USA, LP Foster, Social Hygiene Branch, Tribal Division of Health, 5300 Homestead Rd NE, Albuquerque, NM, USA, V. Gammino, Division of TB Elimination, CDC, 1600 Clifton Rd, MS E-10, Atlanta, GA, USA, and TA Peterman, Division of STD Prevention, Centers for Disease Control and Prevention, 1600 Clifton Rd, Mailstop E-02, Atlanta, GA, USA.

Recent syphilis outbreaks in the US have primarily occurred in large cities among men who have sex with men (MSM). We investigated an outbreak of syphilis on a southwestern American Indian (AI) reservation where risk behaviors are poorly described. Our investigation focused on border town A, where >50% of syphilis cases have been diagnosed since 2002.

Describe the demographics and risk behaviors of syphilis case-patients.

We conducted 1) a retrospective case series study, 2) a name-based cross-match of syphilis case-patients with correctional and treatment facility registries, and 3) a social network analysis for 95 syphilis case-patients (all stages) diagnosed in border town A during January 2000-March 2004. Data were abstracted from medical, health department, and correctional/treatment facility records.

For all syphilis case-patients (n=95), 94% were AI, 76% had early syphilis, 62% were male, and the median age was 40 years (range, 20-85). Patients with early syphilis (n=72) reported a mean of 1.9 sex partners in the three months prior to diagnosis, and 12 of 40 male early syphilis case-patients (30%) reported MSM behavior. Most early syphilis case-patients, both male and female, frequented two local bars, and 62% had a history of alcohol abuse. Almost 70% of syphilis case-patients had been incarcerated—many for alcohol-related reasons—at least once during January 2000-March 2004.

Alcohol abusers, incarcerated persons, and MSM were risk groups for acquiring syphilis. Enhanced screening and prevention programs targeting these populations are warranted.

Additional resources and research activities are needed to develop and implement effective, yet culturally-appropriate, STD interventions in Indian Country.