Nonetheless, the onset of symptoms is variable amongst infected patients, and the interval during which an individual with COVID-19 is contagious remains uncertain. It appears that SARS-CoV-2 can be transmitted prior to the development of symptoms and throughout the course of illness [14]. The infection can involve all age groups, including children, and, moreover, males suffer a disproportionately higher number of deaths than females according to data from cohorts of patients in China, Italy and the United States [15,16]. Patients admitted at the Tongji Hospital, the major endemic area, and positive for COVID-19, showed a median age of over 60-years and a large part (up to 42%) were affected by 1 or more comorbidities, including diabetes mellitus, cardiovascular disease, hypertension, chronic lung disease, cancer, chronic kidney disease, immunocompromising conditions, severe obesity (body mass index ≥ 40) and liver disease [17,18]. Similar evidence was derived from a cohort of 5700 hospitalized patients on the other side of the world, namely in the New York city area in the U.S.A. [15]. Moreover, the data of 333 children with confirmed SARS-CoV-2 from 11 case series were analyzed [19]. Intriguingly, despite the recent evidence that children have the same risk for infection than adults, few cases have been admitted to intensive care units (3%) and only a few deaths have been registered. The less-severe infection has been principally related to the fact that children have a stronger innate immune response and a minor prevalence of comorbidities (arterial hypertension, cardiovascular diseases) than adults [20].