- Under unusual circumstances, such as when breeding birds and their nestlings desert a nest, mites may attack other vertebrate hosts, including humans.
- Insecticide treatment of infested humans and temporary vacation of infested premises are not sufficient to eliminate the problem because adult mites can survive for weeks or months without feeding.
- Identification of bird mites can be attempted with a microscope and illustrations from a standard parasitology text. Because most bird mites are less than a millimetre long, a magnification of 40 to 100 times is necessary for accurate identification.
- Anecdotal evidence indicates that bird mite bites are often misdiagnosed by general practitioners, and the bites are treated as if the problem was scabies or body lice. The problem with misdiagnosis is that treatment of the individual and their clothing and bedding will not eliminate the source of the infestation, and it may recur, requiring further treatment.
- Diagnosis requires information on the circumstances in which the bites occurred, and the nature and distribution of lesions. In difficult cases, an entomologist should be consulted.
Characteristics of bird mite infestation
- Bird mites are barely visible (< 1 mm long) but can be found crawling on the skin.
- The bird mites do not burrow into the skin.
- The bird mites have a characteristic appearance – they can be collected with transparent adhesive tape and recognised with the aid of an identification key and a low power microscope.
- The bites usually produce small itchy papules.
- Source of infestation is usually obvious – such as a bird nest or poultry yard.
Bird mite recommendations
- Collect a sample of the bird mites using adhesive tape as above. Examine the sheet in the morning for white or black specks.
- If you can… identify them using a microscope and illustrations from a standard parasitology text
- If you cant identify consult an entomologist
- Identify, remove & treat the source of bird mites. Nests of birds can be found in roof spaces, on window ledges, in walls’ cavities, in chimneys, around porches, in foundations and basements, etc.
- Use zippered vinyl protectors for incasing box springs, mattresses and pillows. This should be done to prevent infestation.
- Clean the walls, floors and ceiling as often as possible with a good miticide.
- Apply an insect repellent to avoid bird mites’ bites.
- Reduce irritation associated with bird mites’ bites by using an anti-itch lotion or cream.
Laboratory diagnosis of bird mites
Identification by high-power light microscopy, using appropriate taxonomic keys, by an expert is the only method of correctly identifying the mite.
Although Ornithonyssus bursa is the most common mite associated with infestation of homes there are several other mites associated with birds within Australia that can invade dwellings and bite humans.
These bird mites include Ornithonyssus sylviarum (Northern fowl mite) and Dermanyssus gallinae (Chicken mite).
Also, a closely related species, Ornithonyssus bacoti (Tropical rat mite), occasionally attacks humans.
This species is associated with rodents, such as rats and mice, and their nests. Ornithonyssus bursa and Ornithonyssus bacoti are taxonomically very similar and are extremely difficult to differentiate.
Correct identification is absolutely necessary if appropriate control procedures are to be recommended.
Identification of mites and all other medically important arthropods is preformed through the Medical Entomology Department at ICPMR, Westmead Hospital.
The Medical Entomology Department is the only NATA accredited laboratory in Australia for the identification of arthropods of medical importance.
Department of Medical Entomology
Level 3, ICPMR, Westmead Hospital, Locked Bag 9001, WESTMEAD NSW 2145 (02) 9893 8659 http://medent.usyd.edu.au/contact/contact.htm