Is non-severe SARS-CoV-2 infection characterized by early T cell proliferation? The extent of severity of the coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), varies from asymptomatic, mild to severe. Scientists found that during the first wave of the pandemic, individuals infected with non-severe SARS-CoV-2, before the onset of the vaccination program, induced effective host-defense mechanisms in naive populations. To date, little evidence has been documented regarding the immune responses after the onset of the symptoms or virus detection. Further, no cross-sectional studies have been conducted that define the time of infection. Thereby, no report is available that explains the relationship between the earliest immune responses to COVID-19 and temporal kinetics. Scientists believe that understanding the early immune response regarding the asymptomatic or mildly infected population may help determine the factors associated with immune protection in naive populations. This may also provide perceptions about the variants that do not react to the developed vaccines. New research published on the