Food, vaccines, bacteria, and viruses may all prime our immune system to attack SARS-CoV-2
Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), the causal agent of the ongoing coronavirus disease 2019 (COVID-19) pandemic, primarily causes mild to moderate upper-respiratory tract illness. However, some individuals with COVID-19 develop severe infections and require hospital admission.
Source: news-medical.net