Among these 7 variables (gender, SpO2/FiO2 ratio at triage, CCI, respiratory IL-10, viral load, respiratory rate at triage, and age at infection), only CCI, SpO2/FiO2 ratio at triage, gender, and respiratory rate at triage were retained as potential risk factors in the final ordered logistic regression (Figure 5B). Here, IL10 is linked to infection.