"zero COVID-19" . . . "COVID-Zero strategy" . "zero community transmission" . . "Zero-COVID strategy" . . . "elimination strategy" . . "Zero-COVID" . . "suppressing virus transmission" . . . "COVID Zero" . . "zero-COVID policy" . "COVID-Zero" . "zero-COVID" . "elimination strategies" . . . "Covid-free" . . "Zero-COVID" . "strategy of zero COVID-19 transmission" .