House dust mite  
 
 
 

 

     

House dust mite

   
 
 

 

   

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

A house dust mite also called as HDM by some allergists is one of the most common allergen that triggers asthma attack in susceptible individual.

A typical dust mite measures 420 m in length and 250 to 350 m in diameter. It is possible to see house dust mite by a magnifying glass in a well lit place and on a black background.

House dust mite is globular in shape, creamy white in color with striated cuticle. Two main species are American house dust mite (Dermatophagoides farinae) and European house dust mite (Dermatophagoides pteronyssinus). Both species are distributed worldwide and are not necessary confined to Europe or North America.

House dust mite feeds on the organic detritus such as flacks of dead human skin, and flourishes in a humid environment of the homes. Dust mites can be transported airborne by minor air currents generated by usual household activity.

Apart from asthma house dust mites are also responsible for:

  • Itchiness,
  • Running nose,
  • Sneezing,
  • Watery and itchy eyes and
  • Eczema.
  • Important measures that can be taken to control house dust mites are:

    1. Mattress and pillows should be encased in special dust proof covers.
    2. Pillows should be washed every week in hot water. Water must be hotter than 130 F to kill the mites.
    3. Sheets and blankets of your bed should be washed each week in hot water (>130 F).
    4. Carpets should be removed from bedroom and preferably from the house if allergy symptoms are severe.
    5. Sleeping or lying on upholstered furniture to be avoided.
    6. Carpets that are laid on the concrete should be removed.
    7. Indoor humidity should be reduced to less than 50 %.
    8. Stuffed toys must be removed from bed of children who are allergic to house dust mites. These toys should be washed weekly in hot water.
    9. Vacuuming is helpful in removing mite allergens from the carpets but is not able to remove live mites.
    10. Chemical agents are available for killing mites and denaturing mite antigens. However the effects are not dramatic and are not maintained for long periods. Therefore uses of these agents are not recommended routinely (Woodfolk et al. 1995)

     

    Modified on 22-08-2010

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