Monkeypox virus (MPX) is a double-stranded DNA virus that belongs to the Orthopoxviral genera of the Poxviridae family, which is endemic in Central and West Africa. MPX appeared in 1970, since eradication of smallpox. Apparently, smallpox provides a significant cross-protection (>85%) with monkeypox, but probably most important in individuals with recent vaccination (<10 years). It has been suggested that older population (>60 years), vaccinated with smallpox would be partially protected. Nevertheless, this needs further careful assessment. Animal-to-human transmission (zoonotic infection) can occur through contact with blood, body fluids and skin lesions of infected animals such as arboreal and terrestrial rodents (which include squirrels). Long-term exposure to MPX results in human-to-human transmission through droplet infection, contact with an infected lesion or a contaminated object [1]. As per the recent World Health Organization (WHO) declaration, MPX is now treated as a public health emergency of international concern, affecting over 60 000 cases in more than 95 non-endemic countries worldwide, up to 15 September 2022 [2–10]. MPX has currently three clades [11], clade 1 (formerly ‘Congo Basin clade’ or Central Africa clade), clade 2 (formerly West African clade), and clade 3, the new one that contains most genomes from the 2017, 2018 and 2022 human outbreaks. At the clade 3 is included the lineage B.1, the most prevalent among the sequenced genomes of MPX virus in the 2022 outbreak [12]. The clade 1 has been classically related to be the most pathogenic and lethal, leading case fatalities rates up to 10% [13].