BACKGROUND: Single-cell sequencing studies on the lung microenvironment have revealed that the outcome of COVID-19 depends largely on the immune system response rather than the viral load. A robust innate immune response and a regulated adaptive immunity can prevent the worst outcomes such as hospitalization and the need for mechanical ventilation. MAIN BODY: Intriguingly, several vaccines pertaining to the routine vaccination schedule, not only BCG, can skew the immune response towards the aforementioned beneficial effects. SHORT CONCLUSION: This means that routine immunization not only can help in the current pandemic but can also offer a rapid rescue in the subsequent epidemics or pandemics until a vaccine is developed.
Learned lesson from COVID-19: can routine immunizations be the first line of defense against the next pandemic?