MOSQUITO BREEDING (Increase in incidence)

[Mr Speaker in the Chair]

Dr Tan Eng Liang asked the Minister for the Environment if he is aware that for the last few months the incidence of mosquito breeding has greatly increased, pointing to a possible decline in the effective control of mosquitoes by his Ministry; whether this state of affairs is attributable to the recent reorganisation of the vector control services; and why the Vector Control and Research Branch, the expert body, is not directly responsible for directing and supervising the field vector control staff which is at the moment supervised by the District Assistant Commissioners of Environment.

The Minister for the Environment (Mr Lim Kim San): Mr Speaker, Sir, yes, the Ministry of the Environment is aware of the increase in the incidence of mosquito breeding during the last few months. Since March/April this year, we have stepped up our mosquito surveys and control with search and destroy operations. Nine per cent of the 44,530 household premises were found breeding mosquitoes. In construction sites the situation was even worse. Over 50 per cent of some 2,363 construction sites were also found breeding mosquitoes. Over the last three months alone, some 2,000 orders and 350 summonses were served on households and contractors.

The numerous weekly surveys carried out by the Ministry of the Environment have disclosed distinct areas of high incidence of mosquito breeding. Action to eradicate mosquitoes in these areas has commenced with the application of swing-fogging with a non-toxic insecticide into each and every premises. So far about 4,000 premises in Outram Road, Tiong Bahru, Jalan Bukit Merah and Geylang have been so treated. The operation will continue in Rochore and Beach Road areas.

From the above statistics, it can be seen that far from being inactive, as suggested by the Member for River Valley, my Ministry has taken firm action against mosquito breeders.

I am not aware of any recent reorganisation of the vector control services. The control of mosquitoes has always been under the Districts and under the charge of Assistant Commissioners. In 1971, there was a reorganisation of the Vector Control Section of the Districts in that the Sections were brought under the charge of the Senior Public Health Inspectors in charge of cleansing. This was necessary to improve administration and to make vector control more effective as mosquito breeding, as Members are all aware, is related to cleansing of the drains.

The Vector Control and Research Branch is responsible for research and advising the Districts of the various actions to be taken. The Chief Vector Control Officer is the expert and, since April, he has been advising and co-ordinating operations against mosquito breeding by the Districts.

Perhaps it is necessary to explain in detail the type of mosquitoes that we are dealing with. The Aedes mosquitoes, which are the carriers of the Dengue Haemorrhagic Fever, breed in relatively clean water and usually are found in rain water in containers. These are usually found in households, construction sites, and in open spaces, but seldom in polluted, dirty drains. The Culex mosquitoes, which are not the carriers of Dengue Haemorrhagic Fever, breed in polluted water. From the above examples, Members will note that there are thousands of places that these Aedes mosquitoes could breed, and it is near impossible for any authority to carry out a house-to-house search throughout the entire city at any one time, especially when the breeding cycle of mosquitoes is very short, normally one week. The recent increase in mosquito breeding is mainly attributable to the increase in rainfall over the last few months, bad housekeeping in the numerous construction sites as a result of rapid urbanisation, and more generally, the complacency and neglect of the public to take control measures within the premises.

Recently, the Ministry participated in a seminar on "Mosquito Control in Construction Sites" in conjunction with the Singapore Contractors' Association, the Singapore Institute of Architects and the Singapore Institute of Engineers. The aim of these talks is to inform and educate the people involved of the dangers of these mosquitoes and seek their co-operation in eradicating this menace. The Ministry has also been issuing press releases over the last few months on the mosquito situation, but I regret to say that the press reports have not given wide publicity, which they deserve, to the warnings on Dengue Haemorrhagic Fever and also on the necessity to take preventive measures. The most effective means of preventing any outbreak of Dengue Haemorrhagic Fever is, of course, to stop mosquito breeding.

I must reiterate that the control of mosquitoes is very much the duty and responsibility of householders, contractors and, in fact, all of us. Unless the public plays its part, the present outbreak of Dengue Haemorrhagic Fever may get out of control.