Global Influenza Surveillance Network
www.who.int/csr/disease/influenza/surveillance/en/

Purpose
The Global Influenza Surveillance Network is a surveillance system comprised of laboratories and coordinating centers around the world that collect and analyze clinical data and specimens from patients with influenzalike illness during influenza season.38

History and operational characteristics
Established in 1952, the WHO Global Influenza Surveillance Network monitors, collects, and analyzes the influenza viruses that cause seasonal flu throughout the world. These data are used to recommend vaccine strains for seasonal flu and to identify emerging strains of influenza A virus with potential to cause a pandemic. Because of the avian influenza pandemic and increasing concerns about the potential of H5N1 to cause a human influenza pandemic, in 2004 a dedicated H5 Reference Laboratory Network was established to monitor H5N1 viruses. The WHO Global Influenza Surveillance Network works closely with the UN’s Food and Agriculture Organization (FAO), the agency responsible for avian influenza virus surveillance.14,39

The WHO Global Influenza Surveillance Network is comprised of 116 designated National Influenza Centers and 4 designated Collaborating Centers. The WHO National Influenza Centers are located in 87 countries within the 6 WHO regions. Each year during flu season, the National Influenza Centers receive 160,000 samples from patients with influenzalike illness collected by sentinel physicians in the country or region. The Centers perform culture-based virus isolation and preliminarily characterize the isolates with standardized monoclonal antibodies.14 The National Influenza Centers then ship the influenza viruses to one of four Collaborating Centers (located in the U.S., the UK, Japan, and Australia) for detailed genetic and antigenic analysis. The Collaborating Centers are responsible for identifying the predominant circulating viruses as well as genetic drift variants and (occasional) novel influenza viruses.

Each year in February, the WHO convenes the Collaborating Center Directors and representatives of regulatory agencies to review characteristics of the influenza A and B viruses that have been identified and characterized by the Global Influenza Surveillance Network during the previous flu season. Based on these surveillance findings, the experts recommend which virus strains should go into the northern hemisphere (in February) and southern hemisphere (in August) influenza vaccines for the coming flu season.3 The Collaborating Centers also provide vaccine seed strains to influenza vaccine manufacturers.

Region/countries served
Global; all 6 WHO regions are served by National Influenza Centers located in 87 countries.

Funding/budget/staff
Not available