“…Based on reports of non-communicable and communicable diseases, it is possible that COVID-19 vulnerability includes adverse childhood and lifetime experiences (Danese and McEwen, 2012), heritable epigenetic markers linked to ancestral stress (Ambeskovic et al, 2019;Faraji et al, 2017b;Yao et al, 2014), environmental pollution (Chau and Wang, 2020;Hoyt et al, 2020), poor diet (Mozaffarian et al, 2019), and poor social support (Ge et al, 2017;Malcolm et al, 2019;Menec et al, 2020). Each of these factors may be considered a stressor, or a "hit", with potentially cumulative impacts (Daskalakis et al, 2013;Verstraeten et al, 2019b) on COVID-19 vulnerability and complication. Across a single lifespan, the effects of recurrent stress may accumulate (Faraji et al, 2017a), thus increasing the body's "wear and tear" and allostatic load (AL), ultimately heightening the vulnerability to disease in an older individual (McEwen, 2002;McEwen and Wingfield, 2010).…”