The following is a summary of “Predictors of severity of influenza-related hospitalizations: Results from the Global Influenza Hospital Surveillance Network (GIHSN),” published in the August 2023 issue of Infectious Disease by Cohen et al.
The Global Influenza Hospital Surveillance Network (GIHSN) collected data from over 100 clinical sites worldwide since 2012, following a standardized protocol.
Researchers conducted a retrospective study and analyzed global, patient-level data from multiple years using hospital-based surveillance to investigate influenza severity variations across countries. Multivariable logistic regression assessed the risk of intensive care unit admission, mechanical ventilation, and in-hospital death among hospitalized influenza patients. Patient-level covariates and country income were also explored.
The results showed 73,121 patients hospitalized with respiratory illness across 22 countries, with 15,660 confirmed cases of influenza. Accounting for patient-level covariates, investigators found a 7-fold higher risk of influenza-related intensive care unit admission in lower-middle-income countries compared to high-income countries (p = 0.01). Additionally, the risk of mechanical ventilation and in-hospital death increased four-fold in lower-middle-income countries, but it was not statistically significant. Influenza severity increased with older age and comorbidities. After adjusting for patient characteristics, infection with influenza A/H1N1pdm09 was more severe than A/H3N2 across all studied severity outcomes.
Investigators concluded that better vaccine distribution and management can improve flu severity in under-resourced populations and reduce disease burden.