The big question on everyone’s mind is: how long is this going to last?

Of course, no-one knows the answer – but there are a few clues that can help give us some indication.

Firstly the incubation period for the disease is up to two weeks.

What that means is that any social distancing measures would be expected to take about two weeks before they feed through into a reduction in the number of new infections.

Given the social distancing measures – in their most draconian form – were announced on March 23, we would expect to see some slowing of the virus starting to happen.

That appears to be the case from what the chief scientific officer Sir Patrick Vallance has announced, although he rightly said it is too early to be certain.

Of course, the pattern varies across different parts of the country.

I spoke to Philip Astle, the chief executive of the South East Coast Ambulance Service. He said pressure on their services was running about one and half weeks behind London, which suggests the virus may peak a little later in Surrey.

Encouragingly, he said the service was holding up well and they were continuing to attend as normal to ‘non-Covid’ emergencies such as heart attacks and strokes.

I asked him to pass on the thanks of everyone in south-west Surrey for the brilliant work being done by paramedics.

They have a critical job in transferring patients between hospitals so no intensive care units are overwhelmed.

We also have to look at countries like Italy and China to see that the virus does not peak one day and then suddenly decline.

It is likely to remain at peak levels – with, sadly, correspondingly high death rates – for a few weeks.

Then, even if the lockdown is lifted, we have to beware of the virus coming back.

But if we are able to ramp up testing to 100,000 tests a day – a very welcome ambition – we will have a different option next time: rather than locking down the whole country, we will be able to do the rigorous community testing, contact tracing and isolation that has allowed places like Korea, Taiwan, Hong Kong and Singapore to keep their offices, shops and restaurants open.

I know from my time as health secretary how ambitious this new target is.

But this is a time for ambition and I for one will not be betting against the combined skill, ingenuity and determination of our scientists, laboratories and pharmaceutical companies to achieve the impossible at this time of crisis.

* Jeremy Hunt is the MP for South West Surrey and chairs the House of Commons’ health and select committee. He was also formerly the longest-serving health secretary in the history of the NHS.