@RadCentrism Ventilation is probably all you need (apart from a minority of situation where it is impossible). I remain unconvinced that circulation would continue based only on outdoor-level transmission. No circulation = elimination = no prevalence = nothing more needed.
@RadCentrism 通风可能是您所需要的（除了少数不可能的情况）。我仍然不相信仅基于室外级别的传播会继续流通。没有流通=消除=没有流行=不再需要。