Indian Journal of Dermatology
CORRESPONDENCE
Year
: 2015  |  Volume : 60  |  Issue : 3  |  Page : 312--313

Intractable pruritus caused by pigeon mites


Vivek Chauhan, Suman Thakur, Vikram Mahajan 
 Department of Medicine, Dr. RPGMC (Rajendra Prasad Government Medical College), Kangra at Tanda, Himachal Pradesh, India

Correspondence Address:
Vivek Chauhan
Department of Medicine, Dr. RPGMC (Rajendra Prasad Government Medical College), Kangra at Tanda, Himachal Pradesh
India




How to cite this article:
Chauhan V, Thakur S, Mahajan V. Intractable pruritus caused by pigeon mites.Indian J Dermatol 2015;60:312-313


How to cite this URL:
Chauhan V, Thakur S, Mahajan V. Intractable pruritus caused by pigeon mites. Indian J Dermatol [serial online] 2015 [cited 2021 Sep 18 ];60:312-313
Available from: https://www.e-ijd.org/text.asp?2015/60/3/312/156402


Full Text

Sir,

Among the causes of intractable pruritus, pigeon mite or tropical mite infestation is considered to be one, which is rarely diagnosed accurately by the general physicians. Pigeons are found everywhere in India. People are suffering badly from these infestations and in extreme conditions may even lead to mental distress, especially in elderly and children who spend most of their time indoors. A patient presented to OPD with history of intense itch at different sites all over the body lasting for few minutes for past 2 weeks. The pruritus was more prominent during resting hours at home. Similar itch was complained by the other members of the family for same duration. They noted that during the daytime, at office, or at school, there was no itching. The itch used to wake up the children from the sleep. We expected to find the lesions of scabies but the typical web space lesions suggestive of scabies were absent. The children were also examined who showed only few papular lesions on the trunk and some excoriation marks produced by itching. We were not able to isolate any scabies mite from the papular lesions on the skin. Still, keeping a high possibility of scabies, we treated the family for scabies.

Even after 1 week of completion of the scabies treatment, there was no relief of symptoms. The patient returned with some tiny insects, barely visible to naked eye, isolated from the site of itch. He spotted first insect while it was crawling on the trunk of his daughter when she complained of severe itch. The insect was brownish in colour but unable to jump or fly, so it was easy to catch. We examined the insects microscopically and to our surprise, they were the tropical fowl mites also called pigeon mites (Ornithonyssus bursa [Figure 1]). The patient was advised to look for pigeon nests on his roof and remove them. In just 2 days, the family was relieved of the intractable pruritus going on uninterrupted for past 3 weeks.{Figure 1}

Ornithonyssus bursa or the tropical fowl mite, is the most common bird mite that attacks humans but some closely related species coming in human contact are Ornithonyssus sylviarum (Northern fowl mite) and Dermanyssus gallinae (Chicken mite). [1]

The bird mites are barely visible to naked eye and move quite fast on skin. They are transparent and difficult to notice on skin. But once they ingest blood, which gives them color upon digestion, they get easily noticeable to an observant eye. They have a short life cycle of 7 days and can replicate very fast. Pigeon mites lay eggs in the pigeon nests on rooftops of buildings. Larvae emerge from eggs in 3 days and then develop into nymph stages. The nymphs and adults feed on the nestlings when they hatch out of pigeon eggs and are resting in their nests. They feed preferentially on nestlings which are unfeathered. [2] Up to 50,000 mites can be found in a nest. [2] When the birds leave their nests, mites move toward inhabitants of the house. The pigeon mites are harmless as far as the nature of the infestation is concerned. They don't transmit any disease and the bite lesions are short lasting. They are attracted to humans by sensing heat and vibration. [3]

The physicians have very little knowledge about these mites and their effects and so the victims are helpless as they get very little support from medical personnel. Pigeons are found everywhere in India and mostly they roost on the roofs of houses. Mites are not easy to spot, and mostly the victims are unaware of the cause of their intense pruritus, which may lead to unnecessary treatment with various drugs. The problem has a simple solution i.e. finding and removing the nests in the vicinity of house.

Some typical features of bird mites are

Produce pruritus and paresthesiasVisible to observant naked eye once they have taken a blood mealCannot jump or flyCannot survive on human body (or any other mammal), so they do not establish true infestationLimited temporally to spring and early-summer, when nestlings fledge

To conclude, we recommend that physicians should have this entity in their mind when they are diagnosing causes of intense pruritus especially in spring and summer months, especially in people living on top floors. Simply searching for nests and removing them from the vicinity of humans can put an end to an unbearable agony of the victims.

References

1Halliday RB, OConnor BM, Baker AS. "Global Diversity of Mites". In Peter H. Raven and Tania Williams. Nature and human society: The quest for a sustainable world: Proceedings of the 1997 Forum on Biodiversity. Washington DC: National Academies; 2000. p. 192-212.
2Ralph GP. Effects of the haematophagous mite Ornithonyssus bursa on nestling starlings in New Zealand. New Zealand J Zool 1977;4:1.
3Owen JP, Mullens BA. Influence of heat and vibration on the movement of the northern fowl mite (Acari: Macronyssidae). J Med Entomol 2004;41:865-72.