Although some previously published models also suggested delayed resolution with depleted CD8+ T cell responses (Dobrovolny et al., 2013; Miao et al., 2010; Cao et al., 2016; Lee et al., 2009), this bifurcation has not been observed and their estimated delays in recovery do not amount to the long-lasting infections in immunodeficient patients (Wang et al., 2015; Eichelberger et al., 1991; Hou et al., 1992). The gene discussed is CD8A; the disease is infection.