Sarcoptes scabiei
Mites may be more widespread on a baby's skin, causing pimples over the trunk, or small blisters over the palms and soles. In young children, the head, neck, shoulders, palms, and soles are involved. In older children and adults, the hands, wrists, genitals, and abdomen are involved.
Examination of the skin shows signs of scabies. Tests include an examination under the microscope of skin scrapings taken from a burrow.
Jacobson CC, Abel EA. Parasitic infestations. J Am Acad Dermatol. 2007;56:1026-1043.