Regional STD Rates and Trends Among American Indians and Alaska Natives—1998-2007

Background: National STD rates among American Indians and Alaska Natives (AI/AN) are up to 4.5 times higher than rates for whites, with differences even more pronounced at some regional levels.

Objectives: Describe STD rates and trends among AI/AN by region.

Methods: During 1998-2007, we calculated crude annualized rates for chlamydia (CT), gonorrhea (GC), and primary and secondary syphilis (P&S) for AI/AN living in counties on or near reservations in the 12 Indian Health Service (IHS) Areas. Numerators were based on county-level STD cases reported to CDC, and denominators were based on census population estimates. We compared rates with those in the general US population (US). Rates are expressed as per 100,000 population.

Results: In 2007, the overall AI/AN CT rate (732.9) was two times higher than the US rate (370.2). This disparity resulted primarily from high CT rates in four IHS Areas, Aberdeen, Alaska Area, Billings, and Tucson that had rates 3.1 to 5.8 times higher than the U.S. rate. For GC, the overall AI/AN and US rates were similar (107.1 and 118.9, respectively). GC rates were highest in Alaska Area (240.4), followed by Aberdeen and Phoenix Areas (175.8 and 125.4, respectively). For P&S, overall AI/AN and US rates were also similar (3.4 and 3.8, respectively). Several IHS Areas—Navajo, Tucson, Phoenix—had higher than US rates (10.1, 45.0, and 6.7, respectively); four Areas (Alaska, Bemidji, Billings, Nashville) reported no P&S cases in 2007. Since 1998, overall AI/AN rates have remained stable (GC) or increased modestly (CT and P&S), although significant variability exists in regional rates.

Conclusions: AI/AN STD rates vary considerably by region. Further studies are necessary to identify determinants for these differences.

Implications for Programs, Policy, and/or Research: Regional data should be used to guide local STD prevention and control efforts in Indian Country.