Immunoglobulin is released by his immune system and this causes extreme itchiness at the site of the bite. (vetinfo.com)
I have been using dye and fragrance free detergents for the past 5 or so years because I started having mild skin reactions (mostly just extreme itchiness). (thirstiesbaby.com)
Demodex gatoi infection appears to be slightly more common than infection with Demodex cati, and is noted for extreme itchiness. (vin.com)