WHO guideline on public health and social measures for mitigating the risk and impact of epidemic and pandemic influenza

Overview

Influenza virus infections cause acute respiratory illness that is usually self-limiting but can be severe in some cases. Each year, seasonal influenza epidemics cause considerable morbidity and mortality, while influenza pandemics, which occur sporadically when a new influenza virus emerges and spreads in populations which lack immunity against it, are public health emergencies.