DENGUE

Dengue is the most common arbovirus infection in humans. Humans are the main host of the virus, and dengue viruses are transmitted to humans through the bite of Aedes mosquitoes, the most important of which is the predominantly urban species Ae. aegypti (WHO 1993).

There are four serotypes of the dengue virus.

Dengue haemorrhagic fever and dengue shock syndrome are life-threatening complications that are thought to result from a second dengue infection, with a virus different in serotype to that which caused the primary infection (Halstead et al. 1970).

http://www.newscientist.com

Dengue fever is transmitted in Australia by the freshwater breeding mosquito Ae. aegypti (Sutherst 1994). The north and central areas of Queensland are considered potentially receptive to the establishment of dengue. Imported cases are regularly diagnosed in all capital cities.

About 4,000 cases of dengue were recorded in the period 1991-2005.

Climate zones broadly determine the distribution of mosquito-borne diseases (Bergquist 2001), and weather is a major determinant of incidence of disease. Rainfall and temperature are crucial for breeding and replication of the virus. Humidity strongly affects mosquito survival, and hence the probability of transmission

(Sellers 1980; Reiter 1988; Leake 1998).

Transmission of mosquito-borne viruses – such as those that cause the arthritic Ross River and Barmah Forest fevers, Dengue fever, and several forms of the brain-inflaming encephalitis – will probably extend into temperate regions

This is disturbing as the latest outbreak of Dengue fever – which can cause a life-threatening haemorrhagic fever – infected at least 85 people in Cairns in March 2003. And in 2002, Tasmania recorded its largest outbreak of Ross River fever, a disease more often seen in northern Australia. http://www.abc.net.au/health/regions/features/climatechange/

ESTIMATE OF RISK REGION AROUND 2100

2007 DENGUE ZONE 2020 DENGUE ZONE 2050 DENGUE ZONE

if we continue to allow emissions to increase, by 2100: the dengue transmission zone could reach as far south as Sydney A13_s2_1

DENGUE (2)

Indicative direct and indirect health cost items and broader social options for adaptation to reduce the impact of heatwaves and dengue transmission.

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