The when, where, why and how of Asia's deadly Dengue Fever Epidemic*

17 Oct 2007 00:05:03 GMT
Source: Reuters

Oct 17 (Reuters) - Dengue, a mosquito-transmitted disease which causes
fever, headaches and agonising pain in muscles and joints, has killed
389 people and infected more than 38,000 in Cambodia, which is battling
one of the worst outbreaks in years.

Here are some facts about dengue, which poses a threat to 2.5 billion
people, or two-fifths of the world's population, according to the World
Health Organisation (WHO).

WHAT:

-- A severe, flu-like illness, caused by four distinct, but closely
related, viruses. Known colloquially as bone-break fever for the severe
muscle and joint pains it induces, the disease causes death only when it
develops into a more severe form, dengue haemorrhagic fever (DHF).

HOW:

-- Virus-carrying female Aedes mosquitoes infect humans with the disease
when they bite. It takes 4-7 days before a person shows symptoms of the
disease.

-- After incubating the virus for 8-10 days, the black and white striped
mosquitoes can transmit it to susceptible individuals for the rest of
their two-week life span.

WHEN:

-- Dawn and dusk are peak biting times for the silent, aggressive Aedes,
whose name comes from the Greek for "unpleasant". Dengue can peak during
rainy seasons when mosquito eggs hatch in stagnant water.

WHERE:

-- Tropical and sub-tropical regions. Southeast Asia and the Western
Pacific are most seriously affected.

-- More common in urban areas where Aedes like to live, the disease is
endemic in more than 100 countries in Africa, the Americas, the Eastern
Mediterranean, Southeast Asia and the Western Pacific.

HOSPITALISATION:

-- The WHO says there may be 50 million cases of dengue worldwide each
year of which 500,000 are treated in hospital for DHF, many of them
children. At least 2.5 percent of hospital cases die annually.

TREATMENT:

-- With no specific treatment for the four viruses, health officials
focus on eradicating mosquitoes to prevent infections.