Relevance and comparability of global laboratory molecular detection of influenza by the U.S. Department of War, 2025-2026.

Abstract

The U.S. Department of War (DOW)'s Global Emerging Infections Surveillance (GEIS) program conducts influenza surveillance within all geographic combatant commands to enhance U.S. force health protection and military readiness. This report compares laboratory-confirmed influenza data from the GEIS network with the World Health Organization (WHO) Global Influenza Surveillance and Response System (GISRS) from late 2025 through early 2026. Findings from the most recent 2025-2026 respiratory season show that while influenza trends were largely similar, with influenza A/H3N2 predominating, significant differences in percent positivity or subtype ratios emerged in Asia, East Africa, and South America. These discrepancies highlight the unique value of GEIS data, which fills critical surveillance gaps in strategic regions. This targeted surveillance provides crucial insights for mitigating infection risk to U.S. service members, informs annual vaccine strain selection, and ensures an early warning capability for emerging respiratory threats, directly supporting the readiness of the force.