ICD-10 anaphylaxis algorithm and the estimate of vaccine-attributable anaphylaxis incidence in Medicare.

Background: Anaphylaxis is a rare, serious allergic reaction. Its identification in large healthcare databases can help better characterize this risk.

Objective: To create an ICD-10 anaphylaxis algorithm, estimate its positive predictive values (PPVs) in a post-vaccination risk window, and estimate vaccination-attributable anaphylaxis rates in the Medicare Fee For Service (FFS) population.

Comparative Effectiveness of Influenza Vaccines Among US Medicare Beneficiaries Ages 65 Years and Older During the 2019-2020 Season.

Background: Approximately 50 000 influenza-associated deaths occur annually in the United States, overwhelmingly among individuals aged ≥65 years. Although vaccination is the primary prevention tool, investigations have shown low vaccine effectiveness (VE) in recent years, particularly among the elderly. We analyzed the relative VE (RVE) of all influenza vaccines among Medicare beneficiaries aged ≥65 years to prevent influenza hospital encounters during the 2019-2020 season.