Infectious Disease Advisor Among hospitalized adults with severe influenza, A(H1N1) subtype was linked to an increased risk for severe clinical markers, including respiratory distress and intensive care unit admission, when compared with A(H3N2) and B subtypes.
Among patients hospitalized with severe influenza, those with A(H1N1) have more high-risk clinical indicators compared with those with other subtypes, according to study results published in Clinical Infectious Diseases.
Investigators from the United States Centers for Disease Control and Prevention analyzed data for this study from the Hospitalized Adult Influenza Vaccine Effectiveness Network (HAIVEN), whose records are drawn from hospitals in Michigan, Pennsylvania, Tennessee, and Texas. Adults (N=1993) hospitalized with influenza between 2017 and 2020 were evaluated for outcomes on the basis of influenza strain and patient characteristics.