Emerging and re-emerging viral exanthems among children: what a physician should know

Viral exanthems can present with diverse morphologies of rash, including macular, maculopapular, papular, urticarial and vesicular, or sometimes a combination of these. There has been an increasing trend towards emerging and re-emerging viral exanthems in recent years, the cause of which is multifactorial, including changing environmental conditions and altered host-vector-agent interaction. The significant temperature variations brought on by climate change and ever-increasing international travel has modified the host-agent interactions, and many re-emerging viral illnesses are now presenting with atypical presentations, including an increased frequency of affliction across broader age groups and heightened manifestations often posing as 'great imitators' mimicking a myriad of other dermatoses. Although final diagnosis often relies on serological and molecular tests, certain cutaneous clues can help arrive at a probable clinical diagnosis and help the clinicians order specific and relevant investigations, especially in resource-poor settings where access to laboratory diagnostic tests is likely to be limited. In this review we explore the changing disease dynamics of common viral infections, especially in resource-poor settings, including coronavirus disease 2019, chikungunya, hand-foot-and-mouth disease and some newly emerging ones like mpox (previously referred to as monkeypox), and highlight recent developments in our understanding of the clinical variations seen in their presentations.