What happens if a COVID vaccine doesn’t actually work?

Monday’s coronavirus vaccine breakthrough by pharmaceutical giant Pfizer was the best piece of news we have received since the pandemic began.

You might have expected Boris Johnson, someone who finds it difficult to suppress sunny optimism – he’s the man who thought “normality” would be possible by Christmas – to hype up the vaccine.

Johnson chose, however, to fight his natural instincts, stressing it is “very, very early days”.

Speaking at Monday’s Downing Street press conference, he said: “We have cleared one significant hurdle but there are several more to go before we know the vaccine can be used.”

Watch: Johnson welcomes vaccine news but stresses need for caution

So even after this good news, it remains the case that no working vaccine currently exists – and may never exist.

The question remains: what happens if a vaccine doesn’t actually work?

To answer this, it’s worth referring back to a small segment of Johnson’s previous Downing Street briefing, which was held on Thursday last week.

A member of the public, Joe from Shrewsbury, asked the prime minister “what consideration has been given to the possibility of only limited vaccine success?” and, in this case: “how we live with COVID going forward?”

Here is what Johnson said his government will prioritise in the absence of a vaccine.

1. Therapeutics and medicines

Pointing to the discovery earlier this year that the cheap and widely available dexamethasone drug can save patients’ lives, the PM said “therapeutics and medicines” form a key part of the government’s strategy.

“You have seen the progress we have made with dexamethasone and other drugs,” he said. “Dexamethasone has a real impact on people’s outcomes in hospital. So better medicine is very important.”

2. Mass ‘real time’ testing

Johnson pointed to the rollout of mass lateral flow tests, which have a turnaround time of under an hour and help detect asymptomatic cases, stopping people from unknowingly spreading the virus.

The PM said: “The advantage of this approach is you can tell whether people are infectious or not in real time, within 10 or 15 minutes.

“Immediately, without having to worry about the time taken to get the answer from the current testing system, you can help those people to stop the spread of the virus – to self-isolate if they test positive.

“And if they test negative, then of course they are free to do things with other people who test negative in something close to a normal way. That’s the way forward.”

The scheme was piloted in Liverpool last week, with the government announcing on Tuesday that a further 67 areas in England will receive the tests this week.

3. Wait for the weather to improve

Perhaps a less scientific approach than the two listed above.

But the PM insisted: “If you talk to the scientists, they will say that in addition, they believe things will start naturally to improve in the spring for a variety of other reasons, such as the natural rhythm of these viruses and the improvement in weather conditions which will mitigate against the spread of the virus.”

However, he added: “I think the real progress we are going to see is with science. As Chris Whitty often says, there isn’t a virus yet that has threatened humanity that we haven’t beaten by science.”

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