Haze and dust mite allergy in Singapore and Malaysia

In Singapore and Malaysia the two things that set off allergy and asthma most are not pollen: they are house dust mites, all year, and haze, in the dry months of the southwest monsoon. SkyPollen does not yet have a pollen level for either country, because no open pollen forecast exists there; it shows the haze forecast instead.

Today's haze forecast

• Singapore
  PM2.5 100.6 µg/m³
• Johor Bahru
  PM2.5 100 µg/m³
• Kuala Lumpur
  PM2.5 74.9 µg/m³
• Kuching
  PM2.5 27.8 µg/m³
• Penang
  PM2.5 15.9 µg/m³

Today's daily mean PM2.5 by city, CAMS global model (Copernicus), as computed. Model values, not monitor readings.

House dust mites

Dust mites live in mattresses, pillows, sofas and carpets and feed on shed skin; they need humid air, and the tropics give them humidity all year. In a study of Singapore-born adults, 70 to 80 percent of those with measurable allergy antibodies reacted to dust mites, mostly to two species, Blomia tropicalis and Dermatophagoides pteronyssinus, and reactions to anything else were rare (Andiappan et al., Allergy 2014). What helps: mite-proof covers on mattress and pillows, washing bedding weekly at 60 °C, fewer soft furnishings and carpets in the bedroom, and a dehumidifier or air conditioning to keep indoor humidity down.

Haze

Haze is smoke from peat and forest fires, mostly in Sumatra and Kalimantan in Indonesia, carried across the Strait of Malacca and the South China Sea by the southwest monsoon, usually between June and October and worst in dry El Nino years. Its fine particles (PM2.5) reach deep into the lungs. On hazy days: stay indoors with windows shut, run an air purifier with a HEPA filter, use a well-fitted N95 mask outdoors, and keep reliever medication at hand if you have asthma. Check the official readings before going out: haze.gov.sg (National Environment Agency, live hourly readings and advisories); APIMS (Department of Environment Malaysia, live air pollutant index).

Pollen

Pollen allergy exists in the region but is less common than in temperate countries. Grasses and oil palm (Elaeis guineensis), the region's great plantation crop, are known allergens, and people living or working near plantations can become sensitised, but no pollen count or forecast is published for Singapore or Malaysia. When one exists under an open licence, or our own model passes its checks, SkyPollen will show it; until then, no level.

Forecast bars: daily mean PM2.5 from the Copernicus CAMS global model, as computed, against 150 µg/m³. Green is within the WHO 24-hour guideline (15 µg/m³), amber above it, red above the WHO interim target 1 (75 µg/m³). Model values, not monitor readings.

Copernicus CAMS global forecast run of 8 October at 08:00 GMT+8, shown as computed. Not medical advice; see a doctor about allergy testing and treatment.