4, 5 Emerging studies have tended to suggest that COVID-19 susceptibility is related to viral receptors expressed in vivo. 3 Some studies also showed that up to 20% of asymptomatic carriers would experience fatal disease symptoms. Nearly 80% of people infected with COVID-19 were reported to have mild to moderate disease, 13.8% had severe disease, and 6.1% had critical disease. Individuals infected with COVID-19 often have different outcomes.

Unfortunately, the speed of vaccine development often lags behind the rate of virus mutation, causing great disaster to mankind. To fight against COVID-19, home quarantine and investment in epidemic prevention materials have had serious social and economic burdens. 2 The COVID-19 pandemic created a global health crisis of historic proportions and forced governments around the world to impose huge restrictions within and between countries. 1 As of January 11, 2022, confirmed cases were more than 304 million, and deaths were more than 5.4 million. Coronavirus disease 2019 (COVID-19) was prevalent in late 2019 and was caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which has rapidly spread worldwide with the characteristics of rapid transmission and high mortality.

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