varicella-zoster virus reactivation triggered by the second dose of the Pfizer-BioNTech vaccine; This is a literature report.  The patient, a 27-year-old male, received the first vaccination dose on March 16th, 2021 and the second dose on April 10th, 2021. Three days after, two small, itchy, pink papular rashes (< 2 mm) started to develop on the volar aspect of his inner left forearm. Between April 13th and April 16th, the rash became itchier, and the lesions increased in size, reaching 15 mm in diameter, and in number, spreading to the entire left upper limb (Urticarial-like exanthema developed in papulo-vesicular before regressing with scar lesions. The rash started as urticarial like exanthema on April 16th. The left armpit and left upper pectoral region, the volar aspect of the left forearm and the left cubital hollow are shown in these pictures), and involving the left upper pectoral region, the left armpit, the left cubital hollow, the volar aspect of the left forearm, and the dorsal aspect of the second and third fingers. Since the evolution of the symptoms and the related discomfort, the subject contacted his family doctor, who ruled out poison ivy, molluscum contagiosum, scabies, bug bites, and prescribed 40 mg of prednisone, 25 mg of hydroxyzine, and 2% mupirocin ointment. This treatment was started on the evening of April 16th, 2021. After 6 days of treatment, the subject experienced no apparent improvement in either itchiness or skin rash morphology. Indeed, in the following days, the lesions worsened becoming itchier and vesicular, forming blisters filled with serous (On April 22nd, the rash started to spread, and the subject developed vesicular lesions, filled with serous exudates. Vesicular blisters (arrows) filled with serous exudates on the dorsal aspect of the left hand). The aspect of the rash recalled herpes zoster disease and, interestingly, the patient had chickenpox during his childhood when he was 6 years old. After 10 days of treatment without improvement and being concerned about the evolution of the rash, he contacted his doctor again, who prescribed an echocardiogram, which resulted normal. After 18 days (Papular vesicular lesions started to regress and scar lesions developed from April 28th), the papulovesicular rash started to regress, with scar lesions that replaced the vesicles and then, it completely disappeared after 30 days. Details of the lesions are shown (Scar lesions, typical after shingles infection). The papulovesicular rash described in authors' report strongly recalls a varicella-zoster virus reactivation triggered by the second dose of the Pfizer-BioNTech vaccine. Consistent with the Varicella-zoster incubation period, which ranges from 1 to 5 days, the subject started to develop the rash 3 days after the vaccine injection. Also, the evolution of the rash is typical, starting with an urticarial-like papular rash, and becoming vesicular with blisters filled with serous exudates immediately after. Moreover, the lesions developed in the innervation territory of the roots of the left brachial plexus (from C5 to T1 dermatomes) that is in line with the typical shingles presentation, which follows a dermatomal distribution. Although the absence of laboratory tests (varicella-zoster virus-specific IgM antibodies and/or PCR) and histological evaluation, which would confirm the diagnosis, the hypothesis of a varicella-zoster virus reactivation is conceivable. This is further supported by the varicella infection during the subject's childhood. Thus, the present report constitutes the first case documented on a rare case of varicella-zoster virus reactivation on a healthy, young adult male without pre-existing conditions. Despite the impossibility of establishing the causal relation between authors' patient rash and the vaccine, it is reasonable to hypothesize that the vaccination- induced immune stress triggered the varicella-zoster virus reactivation, which is also consistent with the clusters of varicella-zoster virus reactivation already described in COVID-19 patients or in immune-compromised individuals. The incidence of shingles after the COVID-19 vaccine inoculation is not known, more studies are needed to understand how the reactivation of varicella-zoster virus and the Pfizer-BioNTech vaccine are related.  No follow up attempts are possible; Information about lot/batch number cannot be requested. No further information is expected.; Sender's Comments: A contributory role of the product is possible based on the implied temporal association and known safety profile of the product, confounders, and event outcome.