Singapore: number of dengue cases up

[Gert van der Hoek]

More homes breeding mosquitoes, number of dengue cases up

By Hasnita A Majid, Channel NewsAsia |

Posted: 10 May 2007 2033 hrs


SINGAPORE: The National Environment Agency (NEA) has revealed worrying trends about dengue.

For the first four months of this year, the number of dengue hot spots has reached 96.

This is double what was recorded over the same period last year.

NEA is concerned about this and wants the public to do more to bring down the rising numbers.

In April, some 15,000 mosquito larvae were found in homes - a three-fold jump compared to about 4,600 found in February.

Some 400 homes were found to be fertile breeding grounds in April, more than twice the number recorded in February, when about 140 homes were identified as mosquito haven.

It is not even mid May and already, there are over 1,300 (1308) cases of those down with dengue (as of 5 May).

This is high, considering that the total number of cases reported for the whole of last year was about 3,120 - the lowest since 2004.

That year, the number of dengue cases was 9,459 while in 2005, some 14,209 cases were recorded. NEA added that the number of weekly cases is also going up.

Says Satish Appoo, Director, National Health Department, National Environment Agency, "Perhaps our success last year to keep the cases low could have lulled the residents into a sense of complacency but I think we should very quickly snap out of this slumber and get into action and make sure that there is no place in the homes for mosquitos to breed.

"What we would like residents and others to do is to take immediate action to reduce breeding in their homes."

So the NEA has started the second part of what it calls its "Intensified Source Reduction Exercise", where officers will target homes in 44 areas which are prone to outbreaks.

The first part of the exercise, which targets common areas outside HDB flats, showed an improvement in the number of breeding habitats found outside homes.

The NEA however has urged homeowners not to wait until its officers come knocking on their doors before they take action.

It says that home owners should remain vigilant at all times and get rid of stagnant water in common breeding areas such as flower pots and pails.

As at 8 May, 25 dengue clusters - places where there are active dengue transmissions - have been recorded.

The largest clusters are at Jalan Songket / Hougang St 21 with 19 cases reported so far, and Balestier Road / Martaban Road, with 9 cases. - CNA/yy

http://www.channelnewsasia.com/stories/singaporelocalnews/view/275393/1/.html

 

[Commonground]

Re: Singapore: number of dengue cases up

hat-tip bgw in MT

180 new cases of dengue last week
By Pearl Forss, Channel NewsAsia | Posted: 20 May 2007 1753 hrs

http://www.channelnewsasia.com/stories/singaporelocalnews/view/277315/1/.html

180 new cases of dengue last week

SINGAPORE: 180 new cases of dengue were reported last week, an all-time high and mirroring trends in 2005 when the disease hit epidemic proportions in Singapore.

For the first 19 weeks of this year, there were close to 1,500 dengue cases.

That's nearly 50% higher than the corresponding period in 2006.

The Health Ministry says the spike may be due to a new dengue strain in Singapore - dengue 2 which is responsible for 60 percent of all dengue cases here so far.

Singaporeans who have contracted dengue are mostly immune to dengue 1 but they will be susceptible to dengue 2.

Health Minister Khaw Boon Wan said: "There are four strains in dengue. For many years, Singapore's is largely dengue 1, although dengue 2 is quite common in our neighbours. I was in Indonesia recently and I asked them, what's your most common strain and they said dengue 2. So that's the trouble. Within our region, there are different kinds of strains, so presumably, somebody must have brought the virus into Singapore and from there it just spreads."

Already, some hospitals are feeling the crunch as there are limited beds.

The Health Minister said that since the beginning of the year, more than 60 beds have been added, with more to come throughout the year.

But if dengue cases hit epidemic proportions, the number may be insufficient.

So, what can be done to solve the problem?

The government says the National Environment Agency (NEA), Town Councils and grassroots organisations have been activated to search and eradicate potential sources of mosquito breeding in residential areas.

The NEA will also be working with shipyards, construction sites and other industries to stop mosquitoes from breeding.

But the public too will need to do their part.

One example, littering.

Discarded water receptacles contribute to nearly 15 percent of mosquito breeding.

This can be prevented if people just throw their trash in the right places.

Dr Yaacob Ibrahim, Environment and Water Resources Minister, said that he is worried about the situation during the coming school holidays.

"People may be away. If they don't do their part to seal all the toilet bowls.... we may have (dengue) numbers that are not pleasant for Singaporeans," he said.

The Minister appealed to Singaporeans to do their part - check their houses daily for potential breeding areas as it takes about seven days for the mosquito to procreate.

And, one adult female mosquito can lay 300 eggs at one time.

No one in Singapore has died from dengue so far this year. - CNA/ir

 

[Gert van der Hoek]

Re: Singapore: number of dengue cases up

Monday, May 21, 2007

Dengue cases hit record high last week

More hospital beds expected by year end with dengue spike

Jasmine Yin
jasmine@mediacorp.com.sg

THE dengue situation in Singapore has reached fever pitch, with the weekly number of cases hitting 180 last week, an all-time high for this year.
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With a total of 1,488 cases recorded between January and May 12, which is a near 50-per-cent spike over the same period last year, initial signs are pointing to a repeat of the dengue epidemic in 2005, observed Minister for Health Khaw Boon Wan yesterday.
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"We're already quite short of hospital beds and each time there is a surge (in dengue patients), it causes a lot of problems in the hospitals," he said after a community event in Sembawang. Today reported on Friday that occupancy rates at some hospitals were hovering at between 88 and 97 per cent.
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The surge in dengue incidents has been attributed to two factors: Warmer weather conditions, which facilitate breeding of the Aedes mosquito, and the shift in the predominant dengue strain from DEN-1 to DEN-2.
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There are four virus strains, and recovery from one strain does not provide immunity from the other three. DEN-2 is prevalent in regional countries like Indonesia.
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The National Environment Agency (NEA) found 60 per cent of dengue cases from a recent sample to be DEN-2. This shift to a different strain "means a lot of people do not have immunity, like myself", Mr Khaw noted.
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Speaking at a separate event, Environment and Water Resources Minister Yaacob Ibrahim said last week's figure was "too high", 938Live reported.
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"If it goes beyond 200, I think we really have a big problem," said Dr Yaacob.
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By the end of this month, all households will receive a pamphlet, so "really the last piece of the puzzle is the residents", he added.
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Whilst the relevant agencies keep tabs on the outdoor areas, the public can pitch in by checking for potential mosquito breeding grounds inside their homes and by disposing of their trash properly.
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A recent NEA exercise found that litter, such as cans, bottles and packaging material, make up almost 15 per cent of mosquito breeding.
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Meanwhile, more hospital beds can be expected by December and next year, said Mr Khaw. About 70 beds have been added since the start of this year, and he will raise this issue when Parliament sits today.

http://www.todayonline.com/articles/189629.asp

 

[Gert van der Hoek]

Re: Singapore: number of dengue cases up

14 PAP town councils stepping up fight against dengue

23 May 2007 2033 hrs


SINGAPORE: 14 PAP town councils are stepping up on their dengue prevention efforts.

The town councils will be increasing their fogging of dengue hotspots, oiling of drains, cleaning of corridor drains, clearing of choked gully traps and the application of granular insecticide to gully traps.

In addition to these control measures, regular meetings and talks are held with the National Environment Agency to share information on dengue issues.

The town councils are also looking into redesigning improvement projects to ensure that stagnant water does not accumulate. - CNA/yy

http://www.channelnewsasia.com/stories/singaporelocalnews/view/277937/1/.html

 

[Gert van der Hoek]

Re: Singapore: number of dengue cases up

Dengue hits 3 prisons in Sembawang

By Ashraf Safdar, Channel NewsAsia |

Posted: 24 May 2007 2023 hrs

SINGAPORE: Three prison facilities in Sembawang GRC have reported 24 dengue cases, said Health Minister Khaw Boon Wan at an exhibition on infectious diseases on Thursday.

There were 11 cases in Sembawang Drug Rehabilitation Centre, 10 in Khalsa Crescent Prison and three in Admiralty West Prison.

Mr Khaw said the spread of dengue can be controlled if everyone takes simple steps to maintain cleanliness.

In the wake of worrying numbers of dengue cases, the Health Minister urged the public to take a proactive approach to stop the spread of the mosquito-borne disease.

He said: "There are many things which are beyond our control ? weather, strain, Aedes and so on. But there are also many things which are within our control, like keep our houses clean, don't litter, and so on."

Mr Khaw also gave an update on what his ministry has to consider in deciding which insurer to pick as the provider of the revamped ElderShield Policy.

He promised to give more updates on ElderShield by the end of June.

ElderShield is a severe disability insurance scheme to help Singaporeans pay for long-term step down care costs.

Mr Khaw illustrated with an example to show that adding more beds in hospitals was not the most effective solution.

He said: "If an elderly patient comes in for massive orthopaedic surgery, he will, of course, have to stay a few days in the hospital because complications may crop up.

"But once he stabilises, it will take several weeks for the bones to heal and more nursing care, rather than acute medical care, is needed. So for those few weeks, he has a choice ? he can either spend it in Singapore General Hospital or in a community hospital that will charge a much lower rate. I think the choice is straightforward."

The reformed ElderShield will take effect in October and there will be additional products to be offered for those who want higher coverage.

http://www.channelnewsasia.com/stories/singaporelocalnews/view/278190/1/.html

 

[Gert van der Hoek]

Re: Singapore: number of dengue cases up

Singapore's health minister says dengue outbreak worsened by spread of new strain

The Associated PressPublished: May 24, 2007

SINGAPORE: A strain of dengue new to Singapore is impeding efforts to stem the spread of the mosquito-borne disease that has infected hundreds in the affluent city-state this year, a top health official said Thursday.

Health Minister Khaw Boon Wan said the current rise in infections, including a record 210 cases last week and one fatality, evoked memories of a 2005 epidemic that killed 25 in the tropical island-nation of 4.5 million.

"I'm quite worried about the dengue trend," Khaw told reporters on the sidelines of an infectious diseases exhibition.

Authorities said earlier this week that Singapore recorded a nearly 50 percent increase in dengue infections in the first 4-1/2 months of this year compared to the same period in 2006.

Dengue cases reported from the start of January to May 12 rose to 1,488 ? up from 993 in the corresponding period last year, the Health Ministry said.

Singapore defines an epidemic as more than 378 cases a week, local media reported.

The disease, which causes joint pain, high fever, nausea and a rash, is endemic to the region. In severe cases, it leads to internal bleeding and sometimes death.

Khaw said the emergence in Singapore of a different dominant type of dengue was compounding the problem.

"What is a little against us is because of the strain, the strain type. It is ... largely new to the population here," Khaw said. "It's troublesome because many people have no current, existing immunity."

The dengue virus now predominant in Singapore is believed to be the same as in neighboring Indonesia, and is different from the main active strain in Singapore over the past few years, according to local media reports.

Those previously infected with other types of dengue are not immune, and may even face a higher risk of complications when infected with a different strain, The Straits Times newspaper said.

Health officials have been combing public housing estates in search of mosquito breeding sites. Dengue-carrying insects can breed in tiny pools of water found in flower pots, discarded bottles or cans, or old tires.

The Health Ministry said the recent spike in infections is likely due to warmer weather during this period of the year, which is conducive for breeding mosquitoes and the spread of dengue.

http://www.iht.com/articles/ap/2007/05/24/asia/AS-MED-Singapore-Dengue.php

 

[Gert van der Hoek]

Re: Singapore: number of dengue cases up

Wednesday May 30, 2007


Singapore dengue cases jump to new high

SINGAPORE (AP): Singapore recorded a new high in dengue cases last week, government statistics showed, amid warmer weather and the spread of a different strain of the virus.

The city-state last week recorded 259 dengue infections _ the highest weekly incidence this year, breaching the government's "warning level,'' the Health Ministry said Tuesday in a weekly report on infectious diseases.

The outbreak of the mosquito-borne disease has resulted in one fatality so far in the tropical island-nation of 4.5 million. A dengue fever epidemic in 2005 infected thousands and killed 25. According to the Health Ministry, epidemic levels are reached when more than 378 cases are reported in a week.

The disease, which causes joint pain, high fever, nausea and a rash, is endemic to the region. In severe cases, it leads to internal bleeding and sometimes death.

Health Minister Khaw Boon Wan said last week the emergence in Singapore of a different dominant type of dengue was compounding the problem. Warmer weather during this period of the year, which is conducive for breeding mosquitoes and the spread of dengue, is also causing the spike, authorities say.

Health officials have been combing public housing estates in search of mosquito breeding sites. Dengue-carrying insects can breed in tiny pools of water found in flower pots, discarded bottles or cans, or old tires.

http://thestar.com.my/news/story.asp?file=/2007/5/30/apworld/20070530131733&sec=apworld

 

[Commonground]

Re: Singapore: number of dengue cases up

The case of the Fever in Singapore increased, it was worried about was Epidemi

Singapore, (the Analysis)
Several people were infected by the fever was accompanied linu in the foundation and the muscle in this week in Singapore increasingly increased to the highest level while years in recent times, and it was worried about have become the epidemic, said a newspaper here on Wednesday (30/5).
The case of this fever recorded the number 259 in the report last week, said The Strait Times.
This number was the highest figure from the case of the illness in this year, and achieved the 'level' of the 'warning' from 256 to 378 cases like that was appointed by the Ministry of the Health.
The level of the epidemic was achieved whenever more 378 cases of the illness were reported in a week, said the daily and added, the officials of the concerned health that one epidemic possibly could happen in the city country.
The epidemic of dengue fever had happened in Singapore 2005, when 714 cases were reported happened in a week, said The Straits Times.
The epidemic of the fever was accompanied linu in the pivot and the muscle that were caused by the mosquitoes bite also happened in several countries in this region, including Malaysia, Thailand, Pilipina, Indonesia, Vietnam, Cambodia and Myanmar.
The dengue fever virus was spread by mosquitoes aedes aegypti female, that spread the border passage when the tourists were infected resulting from the bite by local mosquitoes that afterwards bit anyone else.
Now did not yet have the vaccine for this illness kind, that his sign like in flu that is casualties experienced the fever and felt linu on all over the of his body.
As a result of this illness could be fatal.
http://analisadaily.com/0-7.htm

 

[Gert van der Hoek]

Re: Singapore: number of dengue cases up

Singapore steps up fight against dengue

www.chinaview.cn 2007-05-31 18:08:06

by Zheng Xiaoyi

SINGAPORE, May 31 (Xinhua) - Singapore has been stepping up a fight against the escalating dengue problem, which has claimed its first fatality here this year.

Five hundred environmental health officers have been assigned to inspect homes islandwide for dengue breeding on a daily basis, and another 150 officers have been tasked to search places like vacant premises and open land.

The city-state's environment watchdog, the National Environment Agency (NEA), said this week that a further 150 staff will be roped in if the situation worsens.

The number of dengue cases has risen sharply in the clean and green country this month, with an average of 167 cases reported each week, about three times the number in the same period last year, according to the NEA.

A record number of 259 cases were reported last week ended May 26, a figure that crossed the "warning level" of 256 cases a week and indicated the number of cases may continue to rise because of the current hot weather, added the NEA.

There have been about 1,800 Singaporeans contracted dengue this year so far, and last month an 85-year-old man died from the disease, which is spread by the Aedes mosquito and is an endemic disease to the tropics.

For the 4.5-million-population island country, the figure was high, considering the total number of cases reported for the whole of last year was about 3,120, the lowest since 2004.

The NEA, along with other government agencies, launched an islandwide anti-dengue exercise last weekend involving almost 100 outreach activities in 60 constituencies. Members of Parliament (MPs) and grassroots leaders made door-to-door visits to spread the message of dengue prevention to residents.

The Singapore government will distribute to 1.2 million homes an educational package, which includes discount vouchers for insecticides and anti-mosquito products.

It also urges the public to do their part to stop the spread of the mosquito-borne disease, calling them to frequently check and remove stagnant water in their homes to get rid of the Aedes mosquito in the coming months.

Changing water in vases and bowls every alternate day and emptying excess water in flowerpot plates daily are some steps advocated by the NEA to households to practise.

But the NEA statistics showed that more public housing flats and condominiums were breeding mosquitoes in the past four months compared with the same period last year.

People will be fined 100 Singapore dollars (about 66 U.S. dollars) if found breeding mosquitoes in their homes for first offense and 200 Singapore dollars (about 130 U.S. dollars) for subsequent breaches.

Singapore's Ministry of Health (MOH) said that dengue cases peak every six years, based on trends. Singapore experienced a dengue epidemic in 2005.

"2006 was clearly seen as an inter-epidemic year" and this year marks the start of a new cycle, "if the trend is left unchecked, disease momentum will cause a worsening situation for 2008 and subsequent years," the MOH said.

Dengue fever has four types of virus, from stereotype 1 to 4. Since December, there has been a shift in the predominant dengue type from DEN-1 to DEN-2.

This could be one of the factors for the recent outbreak, as the immunity among Singaporeans over the past years against DEN-1 virus "offers little or no protection" against DEN-2 virus, the MOH added.

The endemic disease outbreak is not unique to Singapore, and countries in the Asia-Pacific region, such as Indonesia, Malaysia, and the Philippines, have also been hit by similar outbreaks.

According to The Straits Times, a local English daily, at least89 people in the region have been killed by the disease in the first five months of this year.

Dengue killed 44 Malaysians in the first four months of this year while 12,900 residents in Jakarta, Indonesia's capital, had dengue between January and May, the newspaper said.

Dengue is emerging rapidly as one of the most important public health problems in the region. Nearly 1.8 billion people in the region are at risk as compared to an estimated total of 2.5 billion globally, according to the NEA.

http://news.xinhuanet.com/english/2007-05/31/content_6180859.htm

 

[Gert van der Hoek]

Re: Singapore: number of dengue cases up

Number of dengue cases down for the first time in 3 weeks

By Hoe Yeen Nie, Channel NewsAsia |

Posted: 05 June 2007 1933 hrs

Last week, 228 cases of dengue were reported, signalling what may be the start of a downward trend, following rising numbers three weeks earlier.

For the week ending May 26, 259 cases were reported, the highest recorded this year.

While optimistic, Environment and Water Resources Minister Yaacob Ibrahim however stressed on the need to remain vigilant.

He said his Ministry will conduct a refresher course for facility managers of schools, factories and other buildings on spotting dengue-prone spots.

He added that households are the weakest link in the fight to prevent an epidemic of the scale last seen two years ago.

Dr Yaacob said: "We found breeding in (the same) places found in 2005. Palm trees, toilet bowls, in the same places we found in 2005. So what does this mean?

Maybe we're becoming too complacent just because nothing happened in 2006. But dengue, the Aedes mosquito, is a very resilient creature". - CNA/ch

http://www.channelnewsasia.com/stories/singaporelocalnews/view/280409/1/.html

 

[Gert van der Hoek]

Re: Singapore: number of dengue cases up

Second dengue death shows we need to be more alert: Amy Khor

Posted: 12 June 2007 2019 hrs

SINGAPORE: With more dengue cases detected at home, Dr Amy Khor, Senior Parliamentary Secretary, Ministry of the Environment and Water Resources, has urged Singaporeans not to let their guard down.

A second dengue related death was reported on Monday.

293 dengue cases were reported last week, up from 227 cases the week before.

The Aedes mosquitoes are increasingly adaptable and can breed even in a 20-cent coin size pool of water.

Dr Khor said everyone needs to play a part to bring down the numbers.

"We have found home breeding to have increased in the last couple of months. So we really need to make sure that everyone's involved, not just the managers, town councils... not just the pest control people, but also the residents.

"We do not hope that this will revert to what we have seen in 2005 but we really need to take precautions, put in a lot more effort to be vigilant and alert in order to... prevent this from escalating up to 2005 levels," Dr Khor added. - CNA/yy

http://www.channelnewsasia.com/stories/singaporelocalnews/view/281776/1/.html

 

[Gert van der Hoek]

Re: Singapore: number of dengue reaches epidemic levels

Re: Singapore: number of dengue reaches epidemic levels

Dengue reaches epidemic levels, with 401 cases reported last week

By Margaret Perry, Channel NewsAsia | Posted: 19 June 2007 2137 hrs


SINGAPORE: Dengue in Singapore has reached epidemic levels, with 401 cases reported last week ? up more than a third from the week before.

This means that for the first time this year, numbers have crossed the epidemic threshold of 378 cases.

In a joint statement, the National Environment Agency and the Health Ministry blamed the spike on the recent spells of intermittent rain coupled with warm weather.

This has given the Aedes mosquito ample opportunities to breed in minute pools of stagnant water all over the island.

A change in the predominant strain of virus from Den-1 to Den-2 has also led to more cases.

A total of 2,868 cases have been reported in the first 24 weeks of this year, more than double the 1,392 cases in the same period last year.

The NEA has stepped up its checks, especially on homes, and 171,022 inspections were carried out in May.

In the first 23 weeks of the year, 2,354 breeding habitats were discovered in homes, which was 87 percent more than the same period last year.

More than half of the 500 environmental health officers are tackling dengue transmission in the current 77 clusters.

A dengue cluster is formed when two or more dengue cases occur within 14 days and the homes of the dengue victims are within the distance of 150 metres.

A cluster will only be closed when no new case is reported after 14 days of the last dengue case.

The location of clusters with ten or more cases can be found on the NEA website.

Residents living in these areas are advised to take extra precautions such as spraying aerosol in dark corners of their homes, behind the sofas and under the beds early in the morning.

The largest clusters are in Kim Keat Road/Kim Keat Close and West Coast Drive/West Coast Walk, which have 23 cases each.

Doctors said dengue patients usually suffer a lot of discomfort, but many do not need to be hospitalised.

Associate Professor Leo Yee Sin, Head, Communicable Disease Centre, Tan Tock Seng Hospital, said: "The disease has a very low mortality rate most of the time. In other words, it causes very few death cases.

There is still opportunity for us to treat many of the cases adequately in the outpatient setting and to bring the more severe cases to the hospital for management."

http://www.channelnewsasia.com/stories/singaporelocalnews/view/283242/1/.html

 

[Gert van der Hoek]

Re: Singapore: number of dengue cases up

Mosquitoes Have the Edge in Singapore?s Dengue War



By WAYNE ARNOLD

Published: June 27, 2007

SINGAPORE, June 26 ? Under the sink, behind the cleaning detergents, Thurainadan Govindarajoo shined his flashlight into the shadows, searching for telltale signs of the enemy.

?People only think of the obvious places,? he said. ?We?re looking for what I call the hidden habitats.? Under leaking sinks, in disused toilets, beneath potted plants: wherever a few drops of water can linger, mosquitoes can breed.

Mr. Govindarajoo is one of roughly 500 inspectors from Singapore?s National Environment Agency specially trained to conduct house-to-house search-and-destroy missions against Aedes mosquitoes, which transmit the potentially deadly dengue virus. Despite their best efforts, though, the mosquitoes appear to be winning, abetted by the boom in international travel, global warming and their own adaptability.

Singapore and its Southeast Asian neighbors are in the midst of a new epidemic of dengue (pronounced DEN-gay) that is already on course to claim more victims regionally than the last epidemic, in 2005.

Thailand has already had more than 11,000 reported cases so far this year, with 14 deaths, while 48 people have died among Malaysia?s more than 20,000 dengue cases. Sprawling Indonesia, with more than 68,000 reported cases, has had 748 deaths. And while Singapore?s two dengue-related deaths give it the lowest fatality rate in the region, its nearly 3,000 cases make its infection rate second only to Malaysia?s.

Dengue is a relative of yellow fever, hepatitis C and the West Nile virus. It infects an estimated 50 million people a year, and there remains no vaccine or treatment. In acute cases, it causes high fever and debilitating lethargy, accompanied by joint pain so intense that the disease was called ?breakbone fever? when it was first diagnosed more than 300 years ago. About 1 percent of these more serious cases develop hemorrhagic fever or shock, with gastrointestinal bleeding and, in rare cases, brain hemorrhages and death.

Although there are incidences of dengue around the year in tropical climates, cases tend to spike during periods of high rainfall and high temperatures.

If there is a silver lining to Singapore?s dengue problem, it is that it has turned the island state into a global center for knowledge about the disease. As Singapore has promoted itself as a hub for biotechnology research, dengue has quickly become a common cause. In 2004, for example, the pharmaceutical company Novartis opened an Institute for Tropical Disease here, with a specific focus on developing a treatment for dengue.

Nonetheless, results have been slow in coming. ?There?s no quick fix here,? said Paul Herrling, head of corporate research at Novartis.

Dengue is an enigmatic virus, difficult to diagnose and impossible to quarantine. Ninety percent of those infected with dengue develop only mild flulike symptoms, if they feel anything at all, making them unwitting reservoirs for the virus.

Even when symptoms appear, they do so days after the patient has become infectious. And after the onset of dengue?s characteristic fever that varies widely in temperature, antibodies do not appear in significant levels for days, meaning doctors cannot use conventional blood tests to detect the virus until the worst is already over.

Creating a vaccine against dengue might be a simple matter if it were not for another quirk of the virus. Dengue has four known strains, and while infection with one strain appears to provide lifelong immunity against that strain and one of the others, it seems to make a person more likely to hemorrhage if infected with one of the other two strains. Any vaccine, therefore, would have to work simultaneously against all four strains.

Because dengue was long confined to the tropics, it remains a little-understood disease. Experts still do not know precisely how the virus affects the liver or why it causes the level of blood-clotting platelets in the bloodstream to decline.

The virus is spreading fast. Global warming is extending the Aedes mosquitoes? habitat so that dengue has now marched north from Latin America to the southern United States. Commercial aviation is also carrying infected individuals ? and Aedes mosquitoes ? to new areas.

If the virus cannot be blocked or the people carrying it detected and quarantined, the only logical alternative is to thwart the mosquito that transmits it. Singapore?s mosquito control program is widely recognized as the world?s most rigorous. There are widespread public awareness campaigns. Posters around the island now picture a black-and-white-striped, blood-engorged Aedes with a warning: ?If they breed, you will bleed.?

Doctors here are required by law to report dengue cases to the Ministry of Health, which sends the information daily to the National Environment Agency. At the agency, the cases are plotted on an islandwide map in a dedicated dengue situation room. Any area where two cases occur within 14 days of each other in a 150-meter radius is designated a hot spot, and inspectors like Mr. Govindarajoo are dispatched to scour the area for mosquito breeding sites.

The inspectors called to the Indonesian maid at a house in Lengkong, a neighborhood where seven dengue cases had erupted in recent weeks: ?Hello. Good morning. Selamat pagi. Checking for mosquitoes.?

The inspectors fanned out, some climbing ladders to check gutters, while others searched the garden for standing water in potted plants or between the leaves of palm trees.

Aedes aegypti, the most prolific transmitter of dengue, has become ideally suited to the rapidly growing tropical urban environment. Unlike malaria-transmitting mosquitoes that stick to rural areas and swampy waters, it prefers fresh, clean water. It breeds largely indoors, needing only tiny pools of water to lay its eggs. Christina Liew, a medical entomologist at the agency, said Aedes mosquitoes are not as fussy about where they will lay eggs as was once believed. In the absence of clean water, Ms. Liew said, females will lay eggs in polluted water.

?They have learned to adapt to urban situations,? she said.

http://www.nytimes.com/2007/06/27/world/asia/27dengue.html

 

[Gert van der Hoek]

Re: Singapore: number of dengue cases up

Third Singaporean died of dengue


A third Singaporean died of dengue this year, local media reported on Wednesday.

The patient was a 66-year-old Singaporean-Chinese male, who developed a fever on June 15, Channel NewsAsia reported.

He was initially given outpatient treatment, but was admitted into Alexandra Hospital on June 18 after tests showed that he had contracted dengue fever.

Then his condition deteriorated rapidly and despite medical management died one day later.

The second victim who died earlier this month was a 63-year-old man while the first victim this year was an 85-year-old man who died from dengue shock syndrome on May 25.

Singapore's Health Ministry said the country are facing upward trend of dengue epidemic and keeps reminding residents to be vigilant.

According to Singapore's National Environment Agency, more than 3,200 cases of dengue have been reported so far this year, surpassing the total number of cases for the whole of last year of 3,120.

http://english.people.com.cn/200706/28/eng20070628_388203.html

 

[Gert van der Hoek]

Re: Singapore: number of dengue cases up

Dengue cases hit epidemic levels again

By Margaret Perry, Channel NewsAsia

02 July 2007


SINGAPORE: Dengue cases have reached epidemic levels again.

Last week 381 cases were reported, compared to the epidemic threshold of 378.

The previous week, the number of cases had dipped to 349.

According to the National Environment Agency (NEA), one area in Tampines Street 22 is causing particular concern.

Said Silachart Lau, General Manager, North East Regional Office, NEA, "It's quite a rapid growing cluster. In the last 26 days we have seen 20 cases of dengue fever. In a normal situation, we find every new case in three or four days but in this cluster it has doubled."

NEA officers are teaching residents to spray insecticides into dark corners where mosquitoes can breed.

Despite intensive anti-dengue efforts across the island, officers are still finding breeding sites in homes, with pails and dish drainers the most common problem areas.

In its latest update, NEA added that Kim Keat and West Coast are still the areas with the highest number of dengue cases. - CNA/yy

http://www.channelnewsasia.com/stories/singaporelocalnews/view/285787/1/.html