• Decreased number of total CD4+ and CD8+ T cells were observed in most of the patients with further decrease reported in patients who were admitted to ICU.• T cell exhaustion markers like PD1 and TIM3 were higher in severe disease patients.• Serum levels of TNF-α, IL-6 and IL-10 were higher in symptomatic patients. However, no significant changes in the levels of IFN-γ, IL-2, and IL-4 were observed across groups.• T cell count restored and levels of IFN-γ, IL-10, IL-6, and TNF-α decreased as the disease resolved in a subset of patients.