A vaccine is the holy grail in the fight against coronavirus – a simple injection for everyone that will mean an end to lockdowns, social distancing and daily government announcements on death tolls.
Last month UK health secretary Matt Hancock announced a new vaccine taskforce was “working flat out” so that “when a vaccine becomes available, it can be produced quickly and in mass quantities”.
Only there’s a slight catch – “when it becomes available” suggests it’s a certainty, and it’s anything but.
Professor Ravi Gupta, of the Cambridge Institute for Therapeutic Immunology and Infectious Disease, told HuffPost UK: “We need to prepare for a world where we don’t have a vaccine.
“To base public policy on the hope of a vaccine is a desperate measure. We should hope for a vaccine but we shouldn’t expect one in the next year and a half.
“Anyone who says we can is bonkers.”
Boris Johnson sounded a similarly cautious tone on Monday night, when he told the press conference: “I hope, hope, hope that we will achieve a vaccine... [but] this is by no means guaranteed.”
He added: “I believe I’m right in saying that even after 18 years we still don’t have a vaccine for Sars.”
Creating vaccines is a complex and lengthy task at the best of times. Despite nearly 40 years of research, scientists are yet to develop one for the virus that causes Aids.
What is a vaccine?
There are a number of different ways that vaccines can work but what they all have in common is that they harmlessly expose viruses or bacteria to the body’s immune system.
This causes the body to recognise them as dangerous and learn how to resist them. It means that if, the body comes across the infection, it knows how to defend itself.
Why do we need one?
At the moment, not only do we lack a vaccine for the virus that causes Covid-19: we also lack an effective treatment.
Dr Peter English, a consultant in communicable disease control, told HuffPost UK: “We might get better treatments but they’ll only be of use in countries that can afford them, so without a vaccine we’ll be looking at something that’s probably still worse than flu in terms of the number of people who get seriously ill, coming around every winter for the foreseeable future.
″[A vaccine] is the only way we’ll ever get out of this – the virus is out there in the world.
“There’s no way it’s going to be containable. It’s going to race across Africa and India and all the developing countries. There’s no way we can put it back in its box.”
Why do they take so long to make?
Developing any treatment, including vaccines, requires lengthy testing periods on both animals and humans.
“There are lots of different ways of designing vaccines and we’re not sure which one will work for this, if any,” says Prof Gupta.
“Then you have to check it’s safe by injecting into animals and that takes months – then you have to show that it has some efficacy.”
An initial phase one trial is usually carried out on a small group of up to 100 people to make sure the vaccine has no major safety concerns, and to allow scientists to work out an effective dose in humans.
The phase two study is carried out on a larger group of several hundred people to check if the vaccine works consistently and generates an immune response, as well as to look for possible side effects.
Then a much larger phase three study – potentially on several thousand people – can be carried out to allow scientists to gather statistically significant data on a vaccine’s safety and efficacy.
This means looking at whether the vaccine generates a level of immunity that would prevent disease and provide evidence that the vaccine can actually reduce the number of cases.
It also gives a better chance of identifying rarer side effects not seen in the phase two study.
Can’t this be sped up for a global pandemic?
Some parts of the process can, but others simply can’t be rushed.
The Medicines and Healthcare Products Regulatory Agency (MHRA) says given the circumstances it may be possible to overlap the three usual phases of clinic testing and accept less complete data than it would normally expect.
But one of the most important factors to measure for in a vaccine is how long the protection it offers actually lasts. In the case of Covid-19, anything less than a year will not be much use.
And the only way to see if protection lasts a year is to wait for a year after it’s administered during a trial.
Only then can you begin to roll it out to the wider population.
How close are we to a coronavirus vaccine?
A group of Oxford University researchers began clinical trials for a coronavirus vaccine on April 23.
Sarah Gilbert, Professor of Vaccinology at Oxford University, acknowledged nobody can be “completely certain” that it is possible to find a vaccine for Covid-19 – but believes the prospects are “very good”.
Yet even the government’s chief scientific adviser says expectations need to be tempered.
He told the press conference on Monday: “It’s a tough thing to do.”
What about other coronavirus vaccines?
There’s a mixed track record with previous coronaviruses – we’re still not immune to the common cold and vaccines for Mers and Sars, also caused by coronaviruses, were never sufficiently tested to prove their efficacy.
Dr English said: “The science is there and they did a lot of work on Mers vaccine but there wasn’t a market for it. It didn’t affect enough people to warrant the incredible cost of developing a vaccine.”
What if it doesn’t work?
We’ll keep trying.
“Look at the Aids field,” says Prof Gupta. “We’re still trying to make vaccines after 30 years so there’s no answer to that.”
There are options other than vaccines. It’s just that a vaccine would be the ideal – essentially an “inject, forget and get on with your life” treatment for everyone.
Prof Gupta adds: “The alternatives for a vaccine will be antiviral treatments for the disease.
“If we could treat the disease and diagnose it early then you could have a test and a treatment that, if you can start soon enough, you should be able to halt the disease early.
“It might mean you can get infected again but that might be what you have to accept.”
Will life return to normal without one?
This depends on how effective any treatments that are developed are.
World Health Organisation regional director for the Western Pacific, Takeshi Kasai, said in April that people must be ready for a new way of living to allow society to function while the coronavirus is being kept in check.
Speaking to an online press conference, he said we must adapt our lives and health systems along with the epidemic, adding: “At least until a vaccine, or a very effective treatment, is found, this process will need to become our new normal.”
And UK health secretary Matt Hancock admitted on Tuesday we may not be allowed to hug anyone outside our own households until we have a cure or a vaccine – much less go on summer holidays.