Prior viral infection determines the mode and severity of monkeypox virus

OBJECTIVES: Monkeypox (MPox) is a zoonotic virus in the genus Orthopoxvirus. It is transmitted from animal to human, and between humans. The clinical presentations vary, starting with a prodrome phase to different skin findings and systemic complications. METHODS: We present two distinctive cases of MPox co-infected with other viruses (hepatitis C virus [HCV] and HIV) by clinical and histopathological analysis. RESULTS: Surprisingly, the MPox patient with a history of HCV developed different skin pathological characteristics (less severe inflammatory changes than the classic patient with HCV or MPox alone). In contrast, patients living with HIV presenting with MPox had severe inflammatory cutaneous changes and distortion of the skin architecture. CONCLUSION: Our findings strongly suggest that MPox infections likely occur in the presence of one or more previous other viral infections, and the prior infection with specific microbes determines the severity of MPox infection.