Validation of Lactational Mastitis Diagnosis Codes in Electronic Health Care Data.

Background: Electronic health record (EHR) data are an underused source for lactation-related research. The validity of ICD-10-CM-coded lactational mastitis is unknown.

Methods: We assessed lactational mastitis diagnosis code validity by medical record review.

Influenza vaccine effectiveness against hospitalizations and emergency department or urgent care encounters for children, adolescents, and adults during the 2023-2024 season, United States.

Background: The 2023-2024 influenza season had predominant influenza A(H1N1)pdm09 virus activity, but A(H3N2) and B viruses co-circulated. Seasonal influenza vaccine strains were well-matched to these viruses.

Methods: Using health care encounters data from health systems in 8 states, we evaluated influenza vaccine effectiveness (VE) against influenza-associated medical encounters from October 2023-April 2024.

JYNNEOS vaccine safety surveillance in the vaccine safety datalink during the 2022 mpox outbreak in the United States.

Background: The JYNNEOS vaccine (two doses given 28 days apart) was recommended in the United States for people at high risk of exposure to monkeypox virus during the 2022 mpox outbreak. Our objective was to assess the safety of JYNNEOS using two complementary epidemiologic methods.

Methods: This observational cohort included patients of eight large integrated healthcare organizations who received JYNNEOS.

Respiratory syncytial virus (RSV) vaccine effectiveness against RSV-associated hospitalisations and emergency department encounters among adults aged 60 years and older in the USA, October, 2023, to March, 2024: a test-negative design analysis.

Background: Respiratory syncytial virus vaccines first recommended for use during 2023 were efficacious against lower respiratory tract disease in clinical trials. Limited real-world data regarding respiratory syncytial virus vaccine effectiveness are available. To inform vaccine policy and address gaps in evidence from the clinical trials, we aimed to assess the effectiveness against respiratory syncytial virus-associated hospitalisations and emergency department encounters among adults aged at least 60 years.