Here, for the first time, we reported a significant decrease of salivary IL-2 levels, a cytokine that presents both mitogen properties and the ability to induce T cells differentiation to a specific regulatory profile [22], in older adults during the period with social isolation imposed by the COVID-19 pandemic (S2 and S3 time points), when compared to values found before this period (S1). Here, IL2 is linked to COVID-19.