As well as facing an epidemic of Covid are we also facing an epidemic of metaphors? We have ‘the lights from a train in the distance’, ‘moon shots’, ‘beating the goalkeeper’ and ‘hearing the bugle of the cavalry’.

But does the news that a vaccine is 90 per cent effective justify all these colourful turns of phrase?

Jonathan Van-Tam, the deputy chief medical officer, is usually a prophet of doom but he has now suggested the vaccine is ‘like seeing the lights of a train two miles away when standing on a cold and wet platform’. It’s not yet arrived but we’re hopeful.

But, to continue his metaphor, will everyone board the train or will some people decide, on no evidence, that the train is about to derail and refuse to get on board?

Vaccinations are one of the great success stories in medicine but before we give any vaccine, we need to ask two questions does it work and is it safe?

In 1796, Edward Jenner was the first person to publish evidence that immunisations worked.

Smallpox was fatal in 30 per cent of adult cases and 80 per cent of childhood cases. It was killing about 400,000 Europeans a year.

He realised that milk maids who caught the mild disease of cowpox did not appear to suffer from the deadly smallpox.

He then gave a child cow pox and later deliberately inoculated him with smallpox. He remained well, although I would argue about the ethics of his experiment.

Smallpox continued to take its toll.

In 1838, 460 people died of smallpox in Devon although these numbers are probably an underestimate as record keeping was not accurate.

In the 20th century it killed an estimated 500 million people worldwide.

Following the introduction of widespread vaccination, the World Health Organisation was able to declare that the disease had been completely eradicated in 1980.

There are many other vaccinations which have also saved millions of lives.

My grandfather was a GP in Newton Abbot where he saw children die from diphtheria until the vaccination in 1940. Within two years there were hardly any cases. In 40 years in both hospital medicine and general practice I never saw a case of diphtheria.

And now many of my younger colleagues rarely see some of the serious diseases I saw such as measles and whooping cough. I remember a young child who died and others fighting for breath from haemophilus, now prevented by the HIB vaccine.

Unfortunately, from the days of Edward Jenner to the present day there have been ‘anti-vac’ people.

Some based their opposition on religious grounds; if God wants you to die of smallpox we should not interfere.

Others on spurious safety grounds such as the discredited paper by Andrew Wakefield wrongly linking the MMR to autism. We now know that he falsified data and Wakefield was struck off the medical register but not before his dangerous ideas took off and children died from measles.

Others argued for personal liberty. In 1840, vaccination was made free for the poor and in 1853 it became compulsory in Britain.

After demonstrations across the country the government introduced the idea that a ‘conscientious objector’ could refuse vaccination.

The other concern about vaccines is ‘are they safe?’

Any vaccine developed must jump through numerous hoops. To mix a metaphor, the bar is set extremely high.

The phase III trials for new vaccines involve several thousand volunteers and detailed research. This is just a part of the evidence must be submitted to the independent Medicines and Healthcare products Regulatory Authority (MHRA).

No one is suggesting there is no possible risk, but any risk must be compared with the risk of the disease.

After the vigorous assessment from the MHRA I would be absolutely confident that any minute risk from a Covid vaccination is less than the risk of contracting the disease.

When it’s my turn for the Covid vaccine I’ll be first in the queue.

Can we trust Jonathan Van-Tam’s metaphor? Is the train really in sight?

He only appears to have one serious error of judgement. He is a season ticket holder at Boston United so what would he know about beating a goalkeeper?