All you need to know about the house dust mite
For the Curious

House dust mite's life cycle

A female house dust mite may lay 1 to 3 eggs a day. After 6 to 12 days the egg will hatch producing a six-legged larva which will feed then pass through 2 nymphal stages before emerging as an adult to join the colony. Like many animals a growing mite will shed its temporary outer shell-like covering. While a new covering is being formed an immature mite is vulnerable to attack from other mites.
Depending upon environmental conditions house dust mites can live for six to eight weeks. The conditions needed are warm, dark, damp and still with plenty of food available. House dust mites have evolved without sight, but have developed an exquisite sense of smell to search for for food or sensing hormone secretions signalling sex or alarm. When alarmed house dust mites will 'clump' together for protection until the emergency has passed. Clumping has been known to happen when humidity drops dangerously low (below 50%RH) and the colony is threatened with extinction.

A healthy adult mite is up to 75% water and must retain this water balance to breed. House dust mites can produce up to 20 droppings a day, each dropping can containing 14 fully identified potential allergens, many of which are enzymes. House dust mites are a major cause of allergy worldwide.


References

Medical Entomology for Students By Mike Service Published by Cambridge University Press, 2008 ISBN 0521709288, 9780521709286

'Allergens and their role in the allergic immune response', TAE Platts-Mills, JA Woodfolk, "Immunological Reviews' 2011, Vol.242: p 51-68