The haze is back, and with a vengeance. My tickly cough, inflamed throat, smarting eyes and intensely itchy rash on my limbs and torso serve as unsophisticated barometers of the deleterious short-term effects of the recurring menace.

The haze is not just about dust and particles. There is the presence of toxic gases, such as hydrocarbons, too.

The long-term inimical effects of haze would be a monumental challenge for even the most brilliant of epidemiologists to determine with certainty, but one thing is for certain, they would be neither insignificant nor good.

I urge Asean to take decisive action and treat the haze as a multinational calamity.

Jon Yoong (Dr)