Global Alert and Response (GAR)

Lassa fever

Lassa fever is an acute viral haemorrhagic illness caused by Lassa virus, a member of the arenavirus family of viruses. It is transmitted to humans from contacts with food or household items contaminated with rodent excreta. The disease is endemic in the rodent population in parts of West Africa. Person-to-person infections and laboratory transmission can also occur, particularly in the hospital environment in the absence of adequate infection control measures. Diagnosis and prompt treatment are essential.

WHO Collaborating Centre Network

Many of the internationally important outbreaks involve the diverse group of arboviral diseases and viral haemorrhagic fevers. The WHO Collaborating Centres global network of centres for these diseases has collaborating centres in every WHO region and about one third of the centres in developing countries. These centres work in close partnership with WHO and Member States to investigate, confirm and control outbreaks. Through the WHO Collaborating Centre searchable database, information about those centres and laboratories dealing with specifically with Lassa fever is available.

Information resources

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  • 26 February 2015
    Human infection with avian influenza A(H7N9) virus – China
  • 26 February 2015
    Middle East respiratory syndrome coronavirus (MERS-CoV) – Saudi Arabia
  • 23 February 2015
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