June 10, 2007
SE Asia battles dengue surge, climate fears
Southeast Asian nations are battling a surge in dengue cases, amid signs
that climate change could make 2007 the worst year on record for a disease
that often gets less attention than some higher-profile health risks.
The spread of dengue, which is transmitted by the Aedes aegypti mosquito
and is endemic in much of the region, has also accelerated in recent years
due to increasing urbanisation and travel or migration within the region,
Efforts to develop a vaccine are proving difficult because dengue can be
caused by four viruses. So the only real method to fight the disease at
present is to eliminate likely breeding spots for mosquitos from discarded
tyres to plant pots.
"The threat of dengue is increasing because of global warming, mosquitos
are becoming more active year by year and their geographical reach is
expanding both north and south of the Equator," said Lo Wing-lok, an
expert in infectious diseases.
"Even Singapore, which is so affluent and modern, can't exercise adequate
control," Hong Kong-based Lo added. Dengue cases in Hong Kong usually
involve people returning from hotter parts of Asia, but Lo warned that
warmer temperatures meant the disease could ultimately become endemic in
Dengue sufferers often describe the onset of high fever, nausea and
intense joint pain. There is no real treatment, apart from rest and
rehydration, and in severe cases it can be fatal.
In Indonesia, where concerns over bird flu more frequently grab headlines,
dengue saw a dramatic peak earlier this year after much of the Jakarta
area was flooded. "It's not so much the rise in temperature that affects
dengue, rather the rising rainfall has lengthened the lifespan of the
epidemic each season," said Wiku Adisasmito, a dengue expert at the
University of Indonesia.
The Asian Development Bank developed a model suggesting that dengue might
rise three-fold in Indonesia due to climate change. By last month there
had been 68,636 cases and 748 deaths so far this year, according to Health
Ministry data. Although cases are slowing at the end of the wet season,
experts warn that 2006's record 106,425 cases could easily be overtaken.
The record number of deaths was 1,298 in 2005.
Thailand had more than 11,000 cases of dengue fever and 14 deaths by this
month, up 18 percent from the same period of 2006. In May, the worst
month, 3,649 people were found with dengue. Most patients were between
10-24 years old, Deputy Public Health Minister Morakot Kornkasem said in a
The number of dengue cases in Singapore last month was nearly three times
that in the same period a year ago, according to the government, which
says warmer weather was partly to blame. The surge in cases has prompted
the government to step up its anti-dengue campaign, urging Singaporeans to
clear roofs and gutters, and throw out stale water in containers.
Between May 20 and 26, there were 259 dengue cases according to the
Straits Times newspaper, the highest weekly figure this year, but below
the weekly record of 714 cases in September 2005.
In Malaysia, 48 people died from dengue during the first five months of
the year, health officials said, up roughly 71 percent from 2006. By May
26, 20,658 people had caught the disease, a surge of 55 percent over the
corresponding 2006 figure.
"We are concerned over the increase and we need everyone to cooperate with
the authorities to fight the menace," Health Ministry official Hasan Abdul
Rahman told the New Straits Times recently. Prevailing weather patterns of
hot days punctuated by a day of rain have worsened the problem.
"There is no medicine to cure dengue fever, so the only treatment is to
have a lot of electrolytes," said Noranita Badrun, a Kuala Lumpur resident
whose daughter, Nurin Syakilah, spent a week in hospital in April battling
If not diagnosed early, dengue can kill, but Nurin, who received 18
bottles of intravenous fluids during her hospital stay, recovered soon and
is back at school, where two other students also had the disease, Noranita