Global Alert and Response (GAR)

Dengue/dengue haemorrhagic fever

Dengue is the most common mosquito-borne viral disease of humans that in recent years has become a major international public health concern. Globally, 2.5 billion people live in areas where dengue viruses can be transmitted. The geographical spread of both the mosquito vectors and the viruses has led to the global resurgence of epidemic dengue fever and emergence of dengue hemorrhagic fever (dengue/DHF) in the past 25 years with the development of hyperendemicity in many urban centers of the tropics.

Transmitted by the main vector, the Aedes aegypti mosquito, there are four distinct, but closely related, viruses that cause dengue. Recovery from infection by one provides lifelong immunity against that serotype but confers only partial and transient protection against subsequent infection by the other three. There is good evidence that sequential infection increases the risk of more serious disease resulting in DHF.

DHF was first recognized in the 1950s during the dengue epidemics in the Philippines and Thailand. By 1970 nine countries had experienced epidemic DHF and now, the number has increased more than fourfold and continues to rise. Today emerging DHF cases are causing increased dengue epidemics in the Americas, and in Asia, where all four dengue viruses are endemic, DHF has become a leading cause of hospitalization and death among children in several countries.

Currently vector control is the available method for the dengue and DHF prevention and control but research on dengue vaccines for public health use is in process. The global strategy for dengue /DHF prevention and control developed by WHO and the regional strategy formulation in the Americas, South-East Asia and the Western Pacific during the 1990s have facilitated identification of the main priorities: strengthening epidemiological surveillance through the implementation of DengueNet; accelerated training and the adoption of WHO standard clinical management guidelines for DHF; promoting behavioral change at individual, household and community levels to improve prevention and control; and accelerating research on vaccine development, host-pathogen interactions, and development of tools/interventions by including dengue in the disease portfolio of TDR (UNDP/World Bank/WHO Special Programme for Research and Training in Tropical Diseases) and IVR (WHO Initiative for Vaccine Research).

FOR MORE INFORMATION

Highlights

WHO resources for prevention, control and outbreak response Dengue, Dengue haemorrhagic fever

Dengue: guidelines for diagnosis, treatment, prevention and control. New edition 2009

The report of the Dengue Scientific Working Group

Dengue haemorrhagic fever: early recognition, diagnosis and hospital management

An audiovisual guide for health care workers responding to outbreaks
DHF video transcript (80k pdf)

Best practices for dengue control

Environmental Health Project-
Best Practices for Dengue Control in the Americas (PDF-670 K)

Disease outbreaks

  • 30 October 2009
    Dengue fever in Cape Verde
  • 10 April 2008
    Dengue/dengue haemorrhagic fever in Brazil
    Dengue/dengue haemorrhagic fever
  • 17 March 2005
    Suspected Acute Haemorrhagic Fever Syndrome in Angola
    Suspected Acute Haemorrhagic Fever Syndrome