A 34-year-old man presented to dermatology clinic with a lesion on his left palm. The lesion was first noticed 2 weeks before presentation as a nodule with gradual enlargement, accompanied by pain. There was no pruritus or bleeding. He was a shepherd with no prior past medical history. On physical examination, the patient had a 1 × 1.5 cm punched out lesion with peripheral purple discoloration on the medial side of the hypothenar region accompanied by erythema and swelling of surroundings (Fig. 1). Except for a mild fever, there were no other abnormal findings including lymphadenopathy. Routine blood test for tularemia and culture of specimen obtained by skin biopsy ruled out Bacillus anthracis. The histology was consistent with the diagnosis of “orf” that was confirmed later by polymerase chain reaction (PCR).

Fig. 1
figure 1

A punched out lesion with peripheral purple discoloration on the hypothenar region accompanied by erythema and swelling of surroundings

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Orf (also known as ecthyma contagiosum) is a worldwide, parapoxvirus zoonotic infection [1]. Contacts with infected animals or contaminated fomites such as barn doors, fences, or shears can spread the virus to humans [2, 3]. After an incubation period of less than 4 weeks, symptoms appear mostly as skin lesions usually in the hands. It can be itchy or painful, and is sometimes accompanied by lymphadenopathy and systematic manifestations [4]. Differential diagnoses are cutaneous anthrax and tularemia [5]. Orf can be differentiated by skin biopsy and PCR (a non-invasive and pathognomonic method in orf diagnosis). In most cases, the lesions are spontaneously resolved without scarring over 6–12 weeks [2]. Severe disease with atypical lesions and protracted course of illness can be seen in immunocompromised individuals [5]. The latter patients need to be treated with antiviral agents [2].

No antiviral agent or antibiotic was prescribed for the patient, and the lesion healed spontaneously without scarring within 5 weeks.