What is the point of closing parks [LINK] where people are out in the open with fresh air, if they are still going shopping to the shops and supermarkets, where they will be standing inches from each other.
At the same time people will be going on buses, trains and the underground, trapped in an air tight (almost anyway) tin can, sat inches from each other.
The spread may be slowed slightly, but one presumes it will spread as people go to work, shop, and have deliveries sent to them.
The safest way is to simply have zero movement and contact with people for several weeks. But this would mean many going without food. And it would not be practical to stop police, medical staff, fire persons and so on, from going to work.
The irony in this, is all the people who went panic buying, so they could stay home, hoping not to get the virus, while at the same time being crammed into supermarkets with many people.