Hello & welcome, I am Dr. B, a licensed veterinarian and I would like to help you today. I do apologize that your question was not answered before. Different experts come online at various times; I just came online, read about your wee one’s situation, and wanted to help.
Again I do apologize that my colleagues could not aid you sooner. If you would still like assistance, can you tell me:
How long has this been present?
Any changes to the skin (ie pustules, pimples, redness, crusts/scaling, ulcers, or sores)?
Any diet change in the 2 months before this started? Or have you given those possible allergy foods
Is he worse at any particular time of year?
What flea treatment did you use? When did you last apply it?
Since there are a number of issues that could cause this, can you take a photo of what you are seeing with them? That way I can see what you are seeing. To post them, you can either use the wee paper clip on the tool bar above your text box. Or if you cannot see that on your computer/phone, then you can post them on an alternative site (ie Flickr, Photobucket, imgur, etc) and paste the web link here for me to check.