coronavirus alert typography. covid-19 alert. stop covid-19. stop coronavirus. coronavirus warning sign. danger of infection covid

stop warning danger retrovirus immunity covid 2019 virology microbe pneumonia 2019nc0v lock down lockdown safety global health infection prohibition vector caution corona coronavirus icon china flu alert virus fever concept influenza bacterium antibiotics background wuhan diagnosis epidemic biology contagious chinese medical risk location 2019ncov attention biohazard contamination medicine banner disease hazard