Dengue-fever Outbreak Alarms Asia

[george]

Dengue-fever outbreak alarms Asia

People walk past one of many anti-dengue posters erected at bus stops around the island in Singapore.

SINGAPORE: -- The Philippines is stocking up on blood supplies, and Thailand is urging people to sleep under mosquito nets. An unusually severe outbreak of dengue fever has caused alarm across Asia and baffled clean, orderly Singapore with a record 10,000 cases this year.

The U.S. Centers for Disease Control and Prevention considers dengue the "most important mosquito-borne viral disease affecting humans" this year — ahead of malaria and encephalitis — with an estimated 2.5 billion people at risk worldwide.

Across Asia, governments are scrambling to curtail the spread, mainly by educating the public about the potentially fatal illness and controlling mosquito-breeding areas such as stagnant pools.

Dengue is sometimes called bone-breaker's disease because it causes severe joint pain. Other symptoms include high fever, nausea, and a rash. In the worst cases it causes internal bleeding. There is no known cure or vaccine.

Severe outbreak

While outbreaks are common in Asia, the latest has been unusually severe, for reasons that remain unclear.

Dr. Kevin Palmer, a mosquito-borne diseases expert of the World Health Organization who is based in Manila, said Vietnam, Malaysia, Thailand and the Philippines all had a large number of dengue cases this year.

But Palmer is most perplexed by the spike in Singapore.

"It's a city. It has a well-organized health-care system and a preventive system," he said. "It should kick it when it has an outbreak. There's something missing when the cases go very high."

The city-state of 4.2 million had seen 10,237 people sickened by the virus — eight of them fatally — as of Sept. 19. That surpasses the previous record of 9,459 set for all of last year.

Officials have compared the crisis to the 2003 outbreak of SARS, or severe acute respiratory syndrome, that killed 33 here.

"It is baffling," Singapore Health Minister Khaw Boon Wan said.

Hospitals have suspended nonemergency surgery to cope with the large number of dengue patients, and health inspectors are searching public housing for mosquito-breeding areas. Soldiers are dousing their uniforms in a chemical mixture to ward off mosquitoes.

Yaacob Ibrahim, the minister in charge of a high-level committee on dengue, said authorities also were prepared to break into vacant properties to look for mosquito-breeding sites.

Dengue afflicts an estimated 50 million worldwide annually, according to the World Health Organization. Most cases are reported in Africa, Asia and South America. The disease is not spread by human-to-human contact but rather by an Aedes mosquito that has bitten an infected person and then passes the virus to others it bites.

"It is largely a developing world's disease," said Dr. Subash Vasudevan, head of the dengue research unit at the Novartis Institute of Tropical Diseases in Singapore.

Thailand's advice

Thailand is advising people to eliminate sources of stagnant water around the home, to sleep under mosquito nets and to wear repellent, said Chaiporn Rojanawatsirivet of the Public Health Ministry.

Thailand's dengue-fever cases have increased slightly this year, compared with last year, to 32,193 suspected cases, based on clinical diagnoses. The actual number of confirmed dengue cases is probably slightly lower, at around 30,000, Rojanawatsirivet said.

The Philippine government has asked local authorities to intensify educational campaigns about dengue fever, organize mosquito-control systems, ensure sufficient blood supplies for transfusions and increase surveillance of cases.

The disease has sickened at least 18,802 people in the Philippines — a 26 percent rise over last year. At least 259 have died.

In Sri Lanka, a campaign asking residents to keep their premises clean and to empty pots of stagnant water has seen infections there drop to just over 3,000 so far this year from 15,365 for all of 2004.

Indonesia has recorded 38,285 cases of dengue this year, of which 538 have been fatal, said Nyoman Kandun, director general of contagious-disease control at Indonesia's Health Ministry. Last year, almost 60,000 people were stricken with the virus, with 669 fatalities.

Cases are down in Vietnam, but some central provinces are showing an increase because of drought that has forced villagers to keep water in open containers.

Mosquito larvae breed in still water, and experts have said the larvae can "hibernate" in semi-dry conditions.

"It's a mosquito that can survive with minimal water. It's a tough mosquito," said Novartis' Vasudevan.

--AP 2005-10-10

[chownah]

Does anyone know the geographical distribution in Thailand?

[Bates]

This article remembers me of the terrible time I had in 2003. I was on holiday to my gf in Chiang Mai.

After a visit to Doi Suthep I ended up in my apartment with high fever, nauseaness, throwing up and severe bone and musscle pain. I was taken by my gf to the Chiang Mai Ram private hospital. I was taken a blood sample there and doctors founded that I was infected with the Dengue virus. I was a mess, felt like dying..

the Dengue process is 7 days. At first you feel terrible, throwing up, nauseaness, high fever... The amount of bloodcells drops severely from millions to only a couple of thousands. The 4rd, 5th day the disease stabelizes and on the 6th and 7th day you are starting to become ok again. An unforgetable experience for me and made me terrified about mosquitos in Thailand. I ALWAYS wear mosquito milk now. And I can recommend this to anyone visiting Asia.

Cheers

Bates

[cclub75]

This article remembers me of the terrible time I had in 2003. I was on holiday to my gf in Chiang Mai.

<{POST_SNAPBACK}>

could you tell us when in 2003 you were to Chiang Mai ?

[udon]

Does anyone know the geographical distribution in Thailand?

<{POST_SNAPBACK}>

Good question, does anyone know?

[Farma]

The CDC Travellers Yellow book lists Dengue distribution for all of Thailand.

"....As of 2004, dengue fever is endemic in most tropical countries of the South Pacific, Asia, the Caribbean, the Americas, and Africa (see Maps 4-1 and 4-2). Additionally, most tropical urban centers in these regions have multiple dengue virus serotypes co-circulating (hyperendemicity), which increases dengue transmission and the risk of DHF......"

Here's the link to the page including maps.

http://www2.ncid.cdc.gov/travel/yb/utils/y...&obj=dengue.htm

[Farma]

Additional information from the World Health Organisation Thailand website.

http://w3.whothai.org/en/Section8/Section27.htm

"Dengue

Dengue is common everywhere in Thailand below altitudes of 600 meters, including Bangkok. Prevalence is higher in southern Thailand. There is no prophylaxis for dengue, so precautions should be taken to ensure that mosquitoes won’t bite, especially during the daylight hours (repellents are best bet). Transmission of dengue has much to do with how residents of a particular area take care to keep dry any objects that could collect water and serve as breeding sites for mosquitoes. You can find more general dengue information in the WHO Fact Sheet http://www.who.int/inf-fs/en/fact117.html and as well as at http://www.who.int/ith/chapter05_02.html#dengue

[astral]

Do not allow standing water, ANYWHERE in your house or land.

Stock ponds and plant pots with small fish to eat the larvae.

I do not believe spraying helps much. Malaysia and Singapore are hot

in spraying with DDT and still they get Dengue cases

[Abandon]

I live in at the convergence of three canals. What can I do aobut that?

[TAWP]

Two friends got sick some month ago. Both had to be in hospital for some week.

Luckely we have a lot of in-planted fish in all our ponds and water-containers...

Added: And this is in Bangkok...

[udon]

Do not allow standing water, ANYWHERE in your house or land.

Stock ponds and plant pots with small fish to eat the larvae.

I do not believe spraying helps much.  Malaysia and Singapore are hot

in spraying with DDT and still they get Dengue cases

<{POST_SNAPBACK}>

Good advice, and you need to clear up anything which will harbour mozzie eggs within 200meters of your property, so, you need to be on good terms with your neighbours.

Explain to them about empty tins, old tyres etc..

Good luck.

BTW even squeeky clean Singapore has recorded 10,000 cases of Dengue this year.