Chronological classification of pathomorphological lesions in dromedary contagious ecthyma infection

Abstract

An outbreak of camel contagious ecthyma (CCE) occurred in a camel herd of the National Research Centre on Camel, Bikaner, India. The pathomorphological lesions of CCE were classified into 5 different stages on the basis of their sequence of occurrence, nature and duration. In the initial stage, development of erythema and papules which lasted for 1 week, were observed. This was followed by a facial swelling stage which remained for another 1 week, in which swelling on face due to enlargement of mandibular and cervical lymph nodes was observed. In the pustular stage, swelling was subsided and pustules developed on lips, nose, face, eyes and neck region. This stage lasted for 4-5 weeks. In the scab stage, the pustular lesions dried and remained as scab for 1-2 weeks. In the recovery stage, the scab lesions started detaching with formation of grey spots at the affected areas. This stage lasted for 1-2 weeks followed by complete recovery. Histopathology of pustular and scab lesions revealed hydropic degeneration of keratinocytes, hyperplasia of epidermis, hyperkeratosis and intraepidermal pustule with mononuclear cellular infiltration. Intracytoplasmiceosinophilic inclusion bodies were observed in keratinocytes in the epidermis. The total course of the disease in individual camel varied from 8 to 11 weeks. This is the first report on sequential classification of pathomorphological lesions of CCE.