The burden of Staphylococcus aureus among Native Americans on the Navajo Nation

Introduction Native Americans in the southwestern United States have a higher risk for many infectious diseases and may be at higher risk for Staphylococcus aureus due to the high prevalence of risk factors for S. aureus. Recent data on invasive S. aureus infections among Native Americans are limited. Methods Active population-and laboratory-based surveillance was conducted in 2016-2017 on the Navajo Nation to document the rate of invasive S. aureus. A case of invasive S. aureus infection was defined as a Native American individual with S. aureus isolated from a normally sterile body site whose reported community of residence was on or around the Navajo Nation. Results One hundred and fifty-nine cases of invasive S. aureus from 152 individuals were identified. The median age of cases was 56.3 years and 35% were female. Thirty-five percent of cases had community-acquired infections. Ninety-three percent of cases had underlying medical conditions, including diabetes (60%) and obesity (42%), 28% of cases had a documented prior S. aureus infection, and 33% were infected with methicillin-resistant S. aureus. The annual incidence of invasive S. aureus and of invasive methicillin-resistant S. aureus was 64.9/100,000 persons and 21.2/100,000 persons, respectively. Conclusions This community has a high burden of invasive S. aureus infections. Further research is needed to identify prevention strategies and opportunities for intervention.