Inter-Agency Dengue Task Force

LTA’s Role In Dengue Prevention

As a member of the Inter-Agency Dengue Task Force, Land Transport Authority (LTA) actively supports the Government’s efforts to fight against Dengue. Special efforts have been put in on LTA’s construction projects to prevent aedes mosquitoes from breeding.

To address concerns that construction sites might be potential breeding grounds for mosquitoes, LTA and its contractors worked together to step up control on its construction sites. Equal attention was also given to all road facilities such as bus shelters and covered linkways to ensure that public health will not be compromised.

LTA’s Initiatives for Controlling Mosquitoes

The following are the four main methods of control adopted by LTA:

A. Management’s Commitment

  • Recognising the serious health problems associated with dengue fever, management took the initiative to support the nation-wide effort to tackle the problem.
  • Committing manpower to step up vigilance and inspection on all LTA project sites.
  • Committing time for control measures and improved housekeeping.

LTA has also developed and implemented a “zoning method” to better streamline and concentrate its efforts to effectively identify and destroy potential breeding grounds on our sites.

“Seven-Zone Method”

This method is used internally to supplement the external licensed pest control companies who should be combing through the entire site on their visit. This method divides the site into a maximum of seven zones and concentrating efforts in just one zone each day. As the life cycle of mosquito larva takes seven days to reach adulthood, breaking the cycle will prevent the emergence of adult mosquitoes. This method of concentrating focus on just one area each day is much more effective compared to combing through the whole site. This method of control has proven to be quite effective as it reduces the frequency for thermal fogging.

B. Education

The following forms part of the education programme:

  • Prominent display of posters on worksites.
  • Environmental engineers from Safety Division visiting various project offices and division to educate and create awareness amongst project staff and contractors on prevention of mosquito breeding.
  • Daily tool box meetings to educate workers on prevention and personal protection

C. Physical and Chemical Control

  • Identifying sources of stagnating water and eliminating them.
  • Application of anti-mosquito oil and granular larvicides such as “abate”.
  • Filling in of ground depressions.
  • Drilling of holes in walers.
  • Capping or sealing water-filled safety barricades.
  • Regular trimming of grass to deprive mosquitoes of shelters.
  • Topping up tree holes with sand.
  • Increased house-keeping efforts to prevent mosquitoes from breeding on site.

Use of abate in a ground instrumentation point

Water-filled safety barricade with missing filler cap

Water-filled safety barricade with filler cap

D. Monitoring

  • Proper documentation to identify vulnerable areas on site.
  • Stepped up inspections by project team as well as environmental engineers from Safety Division.
  • Use of ovitraps to monitor adult mosquito population.
  • Monitoring of project sites in the vicinity of ‘hotspots’


Roads Facilities

Bus Shelters

LTA also demonstrated its concern for the public by identifying possible breeding grounds in other areas of its operation. The Roads Facilities Division is currently in the process of sealing off gutters in 725 bus shelters. This is being carried out in two phases: the first phase has been completed at the end of last year while the second phase will be completed by March 2006. Future bus shelters will no longer have gutters as they can act as potential breeding grounds for mosquitoes when fallen leaves choke up the gutters.

In the meantime, LTA has deployed contractors to carry out weekly cleaning of gutters on bus shelters and covered linkways as well as application of larvicides to prevent breeding.

Bus shelter without gutters

Public Transport Facilities

In addition to the construction sites, LTA has also taken the initiative to ensure that all MRT/LRT stations and bus interchanges are well guarded against dengue outbreak. Weekly inspections are conducted at various stations, bus interchanges and terminal and appropriate actions are taken where and when necessary to ensure that mosquitoes are not given the opportunity to breed.


LTA is fully committed to the battle against dengue. In addition to the efforts within LTA, last year, 71 staff from LTA also volunteered to spend their weekends helping to comb the various housing estates to eliminate possible breeding grounds for the mosquitoes.

Although the number of dengue cases has subsided, LTA will maintain its vigilance across all areas of its operations and shall spare no efforts in ensuring the safety and health of the public is not compromised. LT

Jan 07