Bangkok (dpa) - Health officials in the US and Europe may soon be
visiting South-East Asia for updates on the most effective means of
fighting dengue fever, traditionally a poor countries' disease.
A dengue outbreak was reported at the beginning of this year in
Madeira, Portugal, and in 2010 there were cases of dengue recorded in
Nice, France.
In 2010, there were also a score of reported cases of locally
contracted dengue in Miami, Florida, the first in five decades.
"Climate change may be responsible but anywhere that it is getting
warmer, the aedes aegypti mosquito will be able to transmit the
dengue virus longer," said Pratap Singhasivanon, dengue expert and
professor in tropical medicine at Thailand's Mahidol University.
The warm South-East Asian region has typically accounted for a
large share of dengue cases worldwide, with the virus normally
peaking during the rainy season. It has been a priority health
challenge for decades.
This year is no exception.
In Thailand, from the start of the year until June 4, a total of
39,029 people have been treated for dengue, a threefold jump compared
to the same period in 2012. At least 44 have died.
Dengue epidemics tend to shift from country to country and year to
year in South-East Asia, as populations build up immunity to one
strain of the virus, then get hit by a different one.
Last year, Vietnam reported 87,000 cases of dengue, up 25 per cent
compared with 2011. There were 79 deaths. During the first five
months of 2013, there were 13,903 dengue cases in Vietnam, down 7 per
cent year-on-year, with only two deaths.
Famously hygienic Singapore has been hard hit this year by its
worst dengue epidemic since 2005. The city-state has recorded more
than 9,000 cases of dengue since January, with two deaths.
Mid-year figures are already twice the number of cases in 2012.
The Jakarta Health Agency said there had been 3,119 known cases of
dengue in the Indonesian capital through May, with seven fatalities.
Malaysia recorded 10,401 dengue cases nationwide through May, up 1
per cent from last year, with 19 deaths, compared with 20 in the same
period in 2012.
The number of dengue cases in the Philippines rose 1.9 per cent to
37,895 through May 25.
"The cases are increasing because the population is increasing,"
said Philippines' Health Undersecretary Teodoro Herbosa. "The urban
centres are increasing, so dengue is one of our public health
problems."
Dengue is transmitted by the aedes aegypti mosquito, an urbanite
that likes to breed in receptacles of standing water that abound in
South-east Asian cities, especially in the rainy season.
The best way to beat dengue is to deprive the mosquito of its
favoured breeding spots.
The Philippines has launched a "4 o'clock habit" campaign, urging
residents to clean their homes each day.
"Nothing beats prevention," Herbosa said.
Malaysia is experimenting with the release of mutant mosquitoes
with fatal genes designed to kill the offspring.
"The trial run will determine how we can control dengue in the
real world," said Rose Nani, chief of Malaysia's Vector-Borne Disease
Station.
Researchers at Singapore's Nanyang Technological University have
developed a mobile phone application which allows residents to
photograph mosquito breeding grounds to send to health authorities.
Thailand has been at the frontline of experimenting with a dengue
vaccine, using school children in Rathchaburi province for trial runs
of the French pharmaceutical firm Sanofi SA's drug.
Initial field tests of the vaccine last year found that it was
only effective in immunizing against three of the four dengue
serotypes.
Further field tests are under way by Sanofi in 10 countries, with
results expected in April.
Research on a dengue vaccine has been underway for the past three
decades, without a breakthrough, partly because of the difficulty of
providing immunity against all four strains of the virus in one drug.
"But I think we will have a dengue vaccine before a malaria
vaccine," Pratap said. "Even if the Sanofi vaccine doesn't work there
are four or five others in the pipeline."
That might be reassuring for rich countries, but a vaccine might
not prove a panacea for South-East Asia.
"Even if the vaccine proves effective, it doesn't mean a dengue
vaccination will be a national programme because we have to take into
account the cost," said Andi Muhadir, director of Indonesia's
Vector-Borne Disease Control Department.
dpa ptb gal jag apa pj tlo rdp
Authors: Pham Trung Bac, Girlie Linao, John Grafilo, Ahmad Pathoni
and Peter Janssen
130205 GMT Jun 13
Copyright 2013 dpa Deutsche Presse-Agentur GmbH