Comparison of human monkeypox, chickenpox and smallpox: a comprehensive review of pathology and dermatological manifestations

AbstractVariola virus, the causing agent of smallpox, was eradicated in 1980s and today no new cases are reported. The first human infectious illness to be eliminated globally is variola. On the contrary to Variola, monkeypox, which is a zoonotic and variola-like disease, has nowadays turned to be a major health problem worldwide. VZV is a neurotropic virus and the cause of varicella (chickenpox) and herpes zoster (shingles), which is also a highly infectious disease, especially prevalent in children. These three skin diseases—monkeypox, smallpox, and chickenpox—are frequently mistaken with one another due to similar manifestations including fever, rash, myalgia, chills and headache, but they can all be distinguished by their distinctive symptoms. Although these rash-causing disorders might present different skin lesions; diagnostic tests can be extremely useful in their differentiation. We searched for these concepts on a search engine like Google Scholar, scanning the results for alternative words and phrases, and examined relevant abstracts or articles for alternative words. The clinical diagnosis of monkeypox infection is commonly made based on the occurrence pattern of its skin rash. It is possible in varicella to concurrently identify lesions in their various stages including macular, papular, vesicular, pustular, and crusts; however, monkeypox lesions are all in the same stage and evolve with the same rate. In this review, we have tried to provide a holistic and comprehensive comparison between these three skin infections with a focus on the newly epidemic monkeypox, bringing about the most recent knowledge about its features and its diagnosis.Keywords: ChickenpoxMonkeypoxrash diseasessmallpoxvaricellavariola viruszoster TransparencyDeclaration of financial/other relationshipsThe authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.AcknowledgementsNone.Data availability statementThe data that support the findings of this study are available from the corresponding author upon reasonable request.Additional informationFundingThis project was supported by the Infectious and Tropical Diseases Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.