DENGUE OUTBREAKS (Update)

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DENGUE OUTBREAKS:

(Update): 3.

Dr Tan Boon Wan asked the Minister for the Environment and Water Resources if he will give an update of (i) dengue outbreaks (ii) the efforts to control it and (iii) further initiatives, if any, in the pipeline.

The Minister for the Environment and Water Resources (Assoc. Prof. Dr Yaacob Ibrahim): Mr Speaker, Sir, according to the World Health Organisation and the International Society for Infectious Diseases, there is a global upsurge in dengue cases this year. In some countries, the total number of dengue cases doubled in the first six months of 2004 compared to the same period last year. In our region, we are seeing the same increase too. WHO had recently issued a dengue alert for Southeast Asia .

As of 18th September this year, a total of 5,248 cases were reported, a 48% increase as compared to the same period last year. Recently, our weekly dengue cases peaked at 332 in the week ending 28th August. This is higher than the weekly peak of 258 cases recorded last year. Although the figure has come

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down to 263 for the week ending 18th September 2004, we are still unable to determine if the situation has stabilised.

Dengue is cyclical in nature. Every year, we see dengue cases building up during the warmer months of July to September. We are now in this traditional peak period. In fact, the weekly average of dengue cases is now 142 cases, as compared to 68 cases reported in the early part of this year. This is also higher than the weekly average of 96 cases reported over the same period last year. Hence, we must continue to be vigilant.

NEA has stepped up mosquito control surveillance, inspecting more than 228,000 premises and conducting more than 21,000 ground surveys since the beginning of this year. This is an increase of 10% over the same period last year. We are seeing some improvements. Today, only 5% of schools inspected were found breeding Aedes mosquitoes, down from 25% before 1999. For construction sites, less than 15% inspected were found breeding mosquitoes. This is down from 30% last year.

The number of households breeding mosquitoes has however continued to increase in recent years. From the 228,000 premises NEA inspected, it is found that 60% of mosquito breeding cases involved indoor breeding. For HDB flats, the number of households found breeding mosquitoes has increased from 6 per 1,000 households in 1999, to 18 per 1,000 last year, and 16 per 1,000 as at 11th September this year. For condominiums, it has more than doubled, from 12 per 1,000 households in 1999, to 26 per 1,000 last year, and 29 per 1,000 households as at 11th September this year. In landed housing, the number has nearly tripled from 19 per 1,000 households in 1999, to 47 per 1,000 last year, and 60 per 1,000 as at 11th September. We must reverse the trend,

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and we can only succeed if we have the cooperation of the community.

For this reason, the NEA initiated a community project known as "Mozzie Attack" in April this year. The aim was to encourage greater community involvement and ownership. Starting with 10 constituencies, household members and maids were trained to detect and eliminate potential breeding sites. The response from the community has been encouraging. To-date, some 2,000 volunteers have been trained on dengue prevention and have become members of the Dengue Prevention Volunteer Groups (DPVG). The number of constituencies involved in the programme has also increased from 10 to 28.

The NEA aims to expand the Mozzie Attack programme to all 84 constituencies over the next 12 months. We hope to see more volunteers coming forward. Only with active community involvement, will we be able to keep the number of dengue cases to the lowest level possible.

Dr Tan Boon Wan (Ang Mo Kio): Mr Speaker, Sir, I would like to ask the Minister whether dengue is running out of control in Singapore. If he looks at the Ang Mo Kio and Yishun areas, the numbers have gone up tremendously. In the last seven years as an MP there, I did not have that many cases but now, almost invariably every week, I see a couple of clusters. This is a deep concern for our residents.

Assoc. Prof. Dr Yaacob Ibrahim: Sir, I agree with the Member that we have to be concerned but I think it is not right for us to say that it is out of control. The situation is well under control. As I mentioned in my reply, we have stepped up enforcement and inspection. In fact, for the Member's constituency, we have checked in the last few weeks and found that there have been no cluster cases.

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We have one or two sporadic cases but there has been no known cluster.

But the point I want to make, Sir, is that once a case is reported, NEA will go in with officers to check and determine whether it is a cluster, and it will carry out the necessary action such as fogging and eliminating the breeding sites. We will continue with the enforcement but, as I mentioned in my reply, we need community involvement. It is difficult for us to say whether the Mozzie Attack is successful but the signs are encouraging. More people are aware of what are the things that they can do. Again, as I mentioned in my reply, the culprits are basically households where indoor breeding contributes 60% of the cases that we have known. We need to get members of the public to be aware and to do the little things that they can do that will help us to keep dengue fever as low as possible.

Dr Tan Boon Wan: Sir, can I ask the Minister how important is fogging as a method to control the Aedes mosquitoes? Is it dangerous to residents? I am quite sure the method kills mosquitoes but how dangerous is it to human beings? This is important because we have to manage the fogging. We cannot overfog an area and there are several agencies, for example, the Government agency could be fogging and the private contractor could also be fogging. So we have to manage the fogging so as not to overfog an area to the consternation of our residents.

Assoc. Prof. Dr Yaacob Ibrahim: Sir, I would like to assure Members that fogging is safe. But having said that, we are very sparing in the way we use fogging. We have to ascertain whether there is a real cluster and whether the population of the Aedes mosquitoes is very high before fogging is used. The

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elements which are used in the fogging are controlled substances. Anybody who wants to use those substances will have to use those which have been registered with NEA. We educate condominium household owners, especially the management committees, on how and when they should use fogging and we ensure that the pest controllers who are involved in the fogging are also trained to use this judiciously.

Mdm Cynthia Phua (Aljunied): Sir, can the Minister let us know, for vacant houses and vacant flats, what are the rights that his officers have and what are the measures that they take to enter these premises to check?

Assoc. Prof. Dr Yaacob Ibrahim: Sir, the Member has raised a very important question because we need to check households when there is a report of a case. When we come across a house which is vacant or locked up, and we cannot enter, we will need to get permission, but we work together with the authorities. Sometimes, the owners may be away or they may be working during the day time, but we will ensure that we will get access into the house one way or the other through legal means to ensure that we can at least go in and do the inspection. We have received calls from the public to inspect some of the vacant premises and we work with the relevant agencies to allow our officers to go into the premises to inspect.

So I would like to assure the Member that when there is a report of vacant premises which may be a potential breeding site, we will obtain the necessary permission for us to enter and inspect the premises and deal with the case.

Mr Zainudin Nordin (Bishan-Toa Payoh): Sir, I would like to know whether, apart from enforcement and education, there is

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any technology that can be used to prevent the breeding of mosquitoes.

Assoc. Prof. Dr Yaacob Ibrahim: I am not sure I would be able to give the Member a good answer. But I think the enforcement and mechanism in which we have in place, which are fogging and clearing of breeding sites, have proven to be effective. But, nonetheless, I take the Member's point that we should continue to investigate new ways in which we can reduce the Aedes mosquito population in Singapore.