Table 1. Definitions of scabies categories, typical distribution, and history features according to IACS Criteria [41].

	Classification	Description
Scabies categories	Clinical–B3 Suspected–C1 Suspected–C2 ‘Any scabies’	Typical lesions in a typical distribution and two history features Typical lesions in a typical distribution and one history feature Atypical lesions or atypical distribution and two history features Any of B3, C1, or C2 combined
Typical Distribution	All ages Aged <2 years	Lesions on the hands/wrists/arms or feet/ankles/lower legs Above, plus lesions on the face/head/neck or abdomen/chest/back
History Features	H1 H2	Itch Positive contact history, defined as one or more of the following: • Close contact with an individual diagnosed with scabies • Close contact with an individual with itch that is not accounted for by another condition

IACS = International Alliance for the Control of Scabies.