“…“Lifestyle” refers to habits (in terms of quality of nutrition, physical activity, drug consumption, smoking) and to socio-economic parameters (access to the health care system, level of education, access to high quality medical information), i.e., the social determinants of health. “Environment” (intended as exposure to contaminants, pollution, and non-ionizing radio frequency, but also as exposure to multiple pathogens) is relevant since it mechanistically modifies the immune response [ 202 , 203 , 204 , 205 , 206 , 207 , 208 , 209 , 210 ]. Viral genetic variants and their effects on virulence/COVID-19 severity are also a matter of intense research [ 211 , 212 , 213 ].…”