A banner has just been hung in my neighbourhood issuing a yellow alert on dengue cases.

The long dry and hotter season means we have to be more aware of the potential spread of dengue.

While everyone has a role to play in preventing mosquito breeding at home, one public area which I find has not received much attention are the multi-storey carparks.

Despite signs reminding people not to wash cars there, I often see domestic helpers washing their employer's cars in these carparks.

Dirt washed off cars flows into the small drains behind each space. Given that motorists often litter in carparks, the drains tend to get clogged or retard the flow of water.

On weekday evenings, there are also people who are paid to go to every level and wash cars parked in the spaces there. This adds to the accumulation of debris in the drains.

The authorities should reinforce the message of discouraging car owners from washing their cars in sheltered parking spaces, or ban the practice.

Every effort needs to be made to keep out dengue.

Chang Yong Yen