660. Are U.S. clinicians thinking measles in the post-elimination era? Surveillance for Measles-Like Illness in a Commercially Insured US Population.
Session: Poster Abstract Session: Public Health: Epidemiology and Outbreaks
Thursday, October 4, 2018
Room: S Poster Hall
Background: In September 2016, the Americas was the first region to eliminate measles, a highly contagious, vaccine-preventable disease that can lead to complications and death. To maintain elimination, the Pan American Health Organization (PAHO) suggested a minimum rate of suspected measles investigations (≥2 per 100,000 population) be conducted annually. However, measles-like illness (MLI) investigations conducted by U.S. clinicians are not tracked by the measles surveillance program in the U.S. To ensure the U.S. meets PAHO standards, we estimated the rate of MLI investigations using a large insurance claims database.

Methods: We used the 2009-2016 Truven Health MarketScan® Databases to identify MLI and MLI investigations. MLI were defined using International Classification of Diseases (ICD)-9/10 diagnostic codes in two ways: a priori, using the Council of State and Territorial Epidemiologists (CSTE) measles case definition or empirically, using ICD codes on insurance claims with a measles diagnostic code. MLI investigations were defined as MLI occurring up to 5 days prior to a measles diagnostic code or billing code for measles serology testing. We computed annual rates of MLI investigations per 100,000 population.

Results: We identified approximately 35.5 million MLI using the a priori definition. Of these, 24,010 had a measles serology code within 5 days; median age was 30 and 51% were aged 18–34 years. Using the empirical definition we identified approximately 46 million MLI. Of these, 29,940 were coupled with a measles serology code; median age was 31 and 50% were aged 18–34 years. The median annual rates for MLI investigations were 3.2 (a priori) and 4.3 (empirical) per 100,000 population.

Conclusion: Maintaining measles elimination requires continued vigilance by clinicians and high-quality case-based surveillance. The estimated rates of MLI investigations in this U.S. population exceeded the PAHO standard, suggesting that the quality of U.S. measles surveillance is robust.

Susannah McKay, PhD, MPH1, Jessica Leung, MPH2, Paul Gastanaduy, MD, MPH2, Janell Routh, MD, MHS2 and Rafael Harpaz, MD, MPH2, (1)Epidemic Intelligence Service, Center for Surveillance, Epidemiology and Laboratory Services, Centers for Disease Control and Prevention, Atlanta, GA, (2)Division of Viral Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, GA

Disclosures:

S. McKay, None

J. Leung, None

P. Gastanaduy, None

J. Routh, None

R. Harpaz, None

Findings in the abstracts are embargoed until 12:01 a.m. PDT, Wednesday Oct. 3rd with the exception of research findings presented at the IDWeek press conferences.