Univariate regression analysis demonstrated that >80 years old, unvaccinated/partially vaccinated, increased WBCs and D-dimer levels, decreased lymphocyte counts and levels of CD3+ T cells, CD4+ T cells, CD8+ T cells, B cells, and NK cells, chronic kidney disease, and cerebrovascular disease were hazard factors for disease progression (Table 2). The gene discussed is CD4; the disease is cerebrovascular disorder.