Global Alert and Response (GAR)

Epidemic intelligence - systematic event detection

WHO global alert and response systematically gathers official reports and rumours of suspected outbreaks from a wide range of formal and informal sources. Formal reports of suspected outbreaks are received from ministries of health, national institutes of public health, WHO Regional and Country offices, WHO collaborating centres, civilian and military laboratories, academic institutes, and nongovernmental organizations (NGOs).

In order to ensure a comprehensive picture of the epidemic threat to global health security, WHO also gathers epidemic intelligence from all informal sources. With the advent of modern communication technologies, many initial outbreak reports now originate in the electronic media and electronic discussion groups.

The Global Public Health Intelligence Network (GPHIN), developed by Health Canada in collaboration with WHO, is a secure Internet-based multilingual early-warning tool that continuously searches global media sources such as news wires and web sites to identify information about disease outbreaks and other events of potential international public health concern. GPHIN is one of the most important sources of informal information related to outbreaks. More than 60% of the initial outbreak reports come from unofficial informal sources, including sources other than the electronic media, which require verification.

As part of Alert and Response Operations, global epidemic intelligence is primarily focussed on communicable diseases (e.g. haemorrhagic fevers, cholera, meningitis, salmonellosis and encephalitis) but also identifies related conditions such as food and water safety, and chemical events.