The UK along with most other countries accepted WHO advice. They monitored the virus as it built up to a certain level, trying to contain it by test and track of those with symptoms. When it got to a certain level it was then decided to require everyone apart from key workers to isolate at home. People were encouraged to work, but only if they could do so without social contact.
The UK entered lock down a little later than Italy or Spain because the virus arrived in force later in the UK. Indeed, the UK virus infection probably was fanned by people holidaying in Italy and returning with it where it was worse earlier than here.
Most argue the lock down has been successful. New cases and the death rate has fallen from shortly after the lock down was imposed, as you would expect. Some query whether the virus started to wane for other unspecified reasons, and some have been critical about the timing of quarantine provisions for visitors from abroad. It should be easy to agree that if you make people stay away from all physical contact with others, it should stop the spread of a contagious disease. As long ago as the medieval period they used isolation hospitals for contagious diseases they could not otherwise cure or control, so it is not a new insight.
Today the issue is different. We know that whilst lock down can decelerate the virus, it will also do substantial damage to livelihoods and businesses. Whilst it is possible to borrow to pay for one lock down period and a business recovery from it, it would become very expensive to try to do so again from a second lock down. The damage would compound and more capacity and more jobs lost for ever.
So from now on government has both to save lives and livelihoods. It both has to bear down on the disease, and help economic recovery. The method has been laid out by Ministers and their advisers. It requires two things. It requires a good test and trace system, which we are assured we now have. It requires the co-operation of the public, who need to submit for a test if they have symptoms, and share details of their contacts if they test positive.
As an enthusiast for getting back to more normal working, I just hope the new model for containing the disease gets the buy in it needs to succeed. We need it to do so to save both lives and livelihoods. I look forward to the NHS establishing isolation centres for residual virus treatment, so the rest of the service can return to normal to start tackling the backlog.