The WHO “Surveillance” page on the Emergencies section explains how the World Health Organization supports disease surveillance in the context of health emergencies. It highlights that effective surveillance systems are essential to detect disease outbreaks quickly in emergency settings, such as during conflicts, natural disasters, or humanitarian crises, so that outbreaks can be identified before they spread widely and cause many deaths. The page also describes WHO’s approaches and tools for surveillance, including standardized data collection on attacks on health care, early warning, alert and response systems, and guidance materials that help countries monitor and analyse health threats, share information, and improve their early detection and response capacities during public health emergencies.