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Pests/mystery bug bites


QUESTION: Would you kindly help me identify mystery bug bites?  Never seen any kind of bug, and the bites are totally unlike flea and mosquito bites I've had.  They are pretty big and red, usually with a raised white center that becomes hard and conical and often turns purple. Some weep fluid.  They itch only mildly, but burn and make muscles ache and systemically ill.  Bites are always widely spaced, never any two are close together, e.g. one "attack" left one bite on ankle, one bite behind knee, one on the buttock and one on stomach. Another attack left just one bite.  Five doctors and the pest control are stumped! They say can't be cat mites or other mites because too widely spaced and big and in past always I've always been able to see fleas and mosquitos. They seem to develop slowly with no clue as to when or where the bite occurred. The only possible clue is our tenant had a cat with a bloody belly and lots of visitors from third world countries. However, we never touched the cat although it invaded our private areas. These episodes have been coming and going for over a year.  Please help!


There are only a few insects and mites that actually bite people, here's a list that you might want to look over. None of these make the kind of lesions/symptoms that you describe. My guess is that these "bites" are not caused by insects or mites but may be some type of allergic reaction, especially since you've not been able to capture or see anything actually bite. Sorry I can't be more specific but you might want to talk with your MD about the possibility of an allergic reaction since these are generally fairly easy to treat.

Jack DeAngelis

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QUESTION: Thank you so much for your prompt and detailed response.  I am inclined to agree it is not bugs, but FOUR dermatologists, an allergist and internist all insist it has to be bugs. Biopsy showed inflammatory response--pretty general.  One of the reasons these doctors were sure it's insects is because my daughter has had the exact same lesions--albeit she only had two "attacks" of them just recently, as opposed to my having more than 10 "attacks" over the last year and a half.  (She and I live together --for the past couple years) Also our handyman had an outbreak of the exact same thing after cleaning the apartment of our tenant with the bloody cat.  Can't think what other agent could get us all! Would it help if I attached an image of the bites?

I don't think I'd be able to tell much from a picture of the lesions since many things can cause similar marks. The only thing I can think that would affect different people in the same area is mold. I believe there are tests for mold but you might check with your local health department. Again, sorry I can't be more specific but I really don't think this is insect or mite related.

Jack DeAngelis


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Jack DeAngelis


I can answer questions in any area of entomology (study of insects, spiders, mites, ticks, and other terrestrial arthropods). Contact me about home and garden insects such as aphids and spider mites, insects that bite and sting such as ticks and wasps, and insects that damage homes such as carpenter ants and termites.


20 years as university extension entomologist, now retired; currently publish a website about home and garden insects.


see Fine Gardening magazine

Ph.D. in Entomology (the study of insects)

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