Wave of optimism as herd immunity forecast

Better days? 12 April marks the second stage of a four step plan to ease restrictions. © Getty

Is this one of the greatest scientific achievements of all time? As the lockdown eases today, one group of experts says the UK has reached a major milestone in its fight against Covid-19.

As dawn broke over England, the country awoke with a sense of anticipation rarely seen on a cold Monday morning.

Shopkeepers hurried to throw open their shutters. On the streets of the capital, eagle-eyed Londoners watched as restaurateurs filled the pavements with tables and chairs. By eight o’clock, queues of shaggy-haired folk, desperate to be free of their lockdown locks, were forming outside the salons.

Just over a year ago, the sight of shoppers milling through the high streets, gym-goers diving into indoor pools and picnickers lazing in the park would not have made headline news.

But today, after months of lockdown, the re-opening of England’s shops, restaurants, hairdressers and gyms is a vital step towards normality.

“On Monday I will be going to the pub myself - and cautiously but irreversibly raising a pint of beer to my lips,” declared Boris Johnson last week.

Today is undoubtedly an exciting day for millions of people across England – the Prime Minister included. But if one group of scientists is right, Monday may prove to be extraordinary for more than one reason.

Last week, researchers at University College London made a stunning prediction: Britain will pass the threshold for herd immunity to coronavirus at some point today, 12 April.

So what exactly does that mean?

Herd immunity occurs when a high percentage of the population can no longer catch a disease – either because they have already had it, or because they are vaccinated. This makes it nearly impossible for the virus to spread.

According to UCL’s model, by today, 73.4% of Britons will be protected from Covid-19. If the model is accurate, this means that deaths from coronavirus will continue to fall, never to rise again.

“It would be an incredible prize, one of the greatest scientific achievements of our times,” writes journalist Fraser Nelson. “It’s not just possible, but probable.”

Not everybody is convinced. Covid-19 is a new disease. The fight against it is a battle filled with countless unknowns. Scientists cannot say for certain how long immunity will last, nor if the vaccine will protect against variants.

And other models are far more pessimistic than UCL’s - last week, advisers warned the government that easing restrictions was “highly likely” to lead to more deaths this summer. So far, the prime minister shows no signs of speeding up his lockdown roadmap.

Still, whether herd immunity is reached today or not, one thing is clear: the UK is surging ahead in the worldwide race against the virus. From a peak of 1,820 on January 20, deaths have fallen by an incredible 95%. By the end of last week, nearly half of all Britons were vaccinated.

Meanwhile, in Europe, many countries are lagging behind. France and Spain have vaccinated just 14% of their populations.

Back in the UK, editor of The Spectator Fraser Nelson remains optimistic: “Herd immunity will (probably) arrive. Maybe not quite on Monday, but soon. And that ought to change everything.”

Is this one of the greatest scientific achievements of all time?

Road to freedom

Of course, say some. The development of multiple vaccines within a year of the emergence of the new coronavirus, and the subsequent rollout across Britain, is clearly one of the most stunning human achievements of all time. It may not have been possible even two decades ago. Achieving herd immunity will spare countless lives and save the economy from untold damage. No other achievement can compare.

Not necessarily, say others. Herd immunity will undoubtedly be a great scientific achievement, but whether or not it is one of the “greatest” is a more complex question. The discovery of electricity in the 1800s changed our lives forever. More recently, the internet overturned the global economy. And what about the humble lever – without which, the Egyptians could not have built the Pyramids?

You Decide

  1. Is it better to be too cautious or too optimistic?
  2. Do people have a moral duty to protect others by having the Covid-19 vaccine?


  1. In pairs, design a poster for a national vaccination campaign in your country. Make sure to include some statistics about both Covid-19 and the vaccines.
  2. Research another great scientific achievement or discovery. Then write and perform a short speech to persuade your classmates that your chosen topic is the greatest achievement of all time.

Some People Say...

“High achievement always takes place in the framework of high expectation.”

Charles F Kettering (1876 – 1958), American inventor and engineer

What do you think?

Q & A

What do we know?
It is generally agreed that the vaccine rollout across the UK has been instrumental to the reduction in coronavirus deaths. Vaccine hesitancy is far lower in the UK than in the USA and Europe. In March, nearly 90% of Britons surveyed said they were willing to have the coronavirus vaccine, compared to less than 50% in France. Meanwhile, one in four Americans say they will refuse the vaccine. Poor take-up of the vaccine could harm many countries’ efforts to achieve herd immunity.
What do we not know?
One main area of debate surrounds whether or not the success of the vaccine rollout and the subsequent decline in cases should lead to a more rapid easing of lockdown restrictions in the UK. After continuous bad news last year, some now say that the Prime Minister has become over-cautious. “Boris Johnson was vaccinated against his own optimism by the third lockdown – and the protection seems to be long lasting,” writes Fraser Nelson. But others say easing the lockdown too soon is far too risky.

Word Watch

Crucially, herd immunity protects people who cannot be vaccinated, such as the very young or very sick.
UCL’s model is based upon real-time death, infection, hospital admission and vaccination statistics. It also looks at vaccine effectiveness and mobility trends, which affect transmission.
The model predicts that deaths will continue to fall until 24 May and then stay at a low and stable rate without a summer spike.
There are thousands of variants of the Covid-19 virus. Only a few cause concern. In the future, vaccines may need to be tweaked so they are still effective against new variants.
This model was produced by the Scientific Pandemic Influenza Group on Modelling (SPI-M), which gives advice to the UK government.
Lockdown roadmap
Today marks the second stage of a four stage lockdown easing process in England. If it goes ahead as planned, all legal limits on social contact will end on 21 June.
The Spectator
The Spectator is a weekly British magazine on politics, culture and current affairs. It was first published in 1828, making it the oldest weekly magazine in the world.
Nelson points to studies suggesting the Pfizer vaccine offers 100% protection against the South African variant.

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