COVID-19: What does it take to vaccinate 13 million people in six weeks?

·8-min read

Boris Johnson has promised to vaccinate more than 13 million people by the middle of February, but experts say it will be an "ambitious" challenge.

Around 1.3 million people in the UK have now received one of the two vaccines currently being rolled out, but the distribution effort will have to be scaled up significantly if the target is to be reached.

So far, the most that have been put in arms in the course of a week is around 610,000 doses, but the government plans to ramp that up so, potentially, two million doses a week will be distributed.

The 13.9 million total that is needed, according to COVID vaccine minister Nadhim Zahawi, is made up of all residents in care homes and their carers, everyone over 70 years old, all frontline healthcare and social care workers and everyone who is clinically extremely vulnerable.

So, how will they get there and what may be some of the hurdles the effort will have to overcome?

1. Manufacture

Currently, two vaccines have been given approval to prevent COVID-19 in the UK: the Pfizer/BioNTech vaccine, which was approved in early December and the AstraZeneca/Oxford candidate which was licensed in late December.

The Pfizer vaccines destined for the UK are manufactured in Belgium.

They're produced in vials which contain about five doses each, diluted with standard pharmaceutical-grade saline solution.

The vials are placed in trays of around 100, and these trays are stacked in bespoke freezer boxers which are colloquially known as "shippers".

Because the vaccines are based on messenger RNA (mRNA) molecules enveloped in a lipid nanoparticle - something that is very easily destroyed - they need to be stored at a very cold temperature to prevent them from degrading, so they have to be kept at -70C.

Once thawed, they can be stored for up to five days in a fridge.

AstraZeneca, which has the capacity to make vaccines in the UK, will get its initial doses from Netherlands and Germany, due to a "quirk of the programme".

Ian McCubbin, manufacturing lead for the government's vaccine taskforce, said the vast majority of the 100 million doses it will produce for the UK will be made in Britain, with only those needed right at the start of the rollout coming from Europe.

Two firms, Oxford BioMedica and Cobra Biologics will make the vaccine with another firm, Wockhardt, providing what is known as "fill and finish" capability.

Getting the vaccines that are produced abroad to the UK should not be a problem as the government has said it will provide military aircraft in the event of blockages.

The vaccines makers have said it will not be manufacturing capacity that will prevent the government reaching its target.

Pfizer said on 2 January that "deliveries are on track" and a key member of the AstraZeneca team told The Times it will be able to supply two million doses a week by the third week of January.

But the so called "fill and finish" part of the process could continue to hold up supplies, with England's deputy chief medical officer Jonathan Van-Tam saying a shortage of materials needed to produce and package vaccines could slow down the national rollout.

For this and other reasons, chief medical officer Chris Whitty warned at the end of last week vaccine shortages were likely to cause problems for "several months".

It has led the British Medical Association to say it needs "a guarantee" that supply lines are in place.

2. Distribution/logistics

The biggest factor in distributing the vaccines is the temperatures they have to be stored at, with AstraZeneca being much easier to store and transport.

Whereas the Pfizer option needs moving in trays, which are then stacked in temperature controlled freezer boxes that hold between 1,000 and 5,000 doses each, with dry ice being used to keep the interiors of the boxes cold, the Oxford/Astra candidate can be kept at fridge temperature (2C to 8C).

Since the Pfizer jab started to be distributed, the government has built up a network of vaccination centres and hubs, with around 730 so far.

Boris Johnson says there will be around 1,000 by the end of the week but experts say more will be needed if enough people are to be reached.

The healthcare sector is also urging a sizeable upscaling in the number of distribution points.

The Pharmaceutical Services Negotiating Committee (PSNC), which represents pharmacists working on the front line, said a better national plan was required.

PSNC chief executive Simon Dukes, told Sky News: "If it is to achieve the government's ambitious COVID-19 vaccination plan, we believe the NHS must look to community pharmacies.

"Pharmacies have a great track-record in vaccinations. Although some pharmacies are already up and running delivering COVID-19 vaccinations there is as yet no national plan to let pharmacies vaccinate their local communities: the NHS and government must now set out this plan.

"Pharmacies have been open throughout the COVID-19 pandemic offering healthcare advice close to people's homes: we must now make the most of this formidable healthcare network to help with this latest challenge."

3. Administration

Once the vaccines have made it to the distribution points, they still have to be put into people's bodies.

Some have claimed it is similar to the effort required to inoculate adults every year against influenza, but for flu the UK usually reaches only around 70-75% coverage of the key demographic of the over-65s, according to Prof Nilay Shah, of Imperial College London, which is around nine million people out of 12 million in total. He adds that this is usually achieved over the period from September to January, five months.

A number of commentators have said that it could be a lack of qualified staff that holds up distribution.

This an increasingly acute issue as healthcare workers themselves become affected by ballooning COVID infection rates across society as a whole.

But doctors themselves say there could be a range of other factors that could slow the process down.

Dr Richard Vautrey, the British Medical Association's GP committee chair, said: "To reach this target within the time frame set out by government there will need to be a step-change to administer around the approximately 2 million vaccines per week needed.

"Once they have supplies, GPs need to be given the flexibility to let them focus on the vaccination campaign as a priority, and there must be honesty around what services will need to be paused to allow this to happen.

"Crucially, we need to be able to deliver vaccines from as many practices as possible, rather than larger sites - and with the launch of the AstraZeneca vaccine NHS England must allow us to do so.

"We also need a clear and consistent national vaccination plan, a reliable IT system, and bureaucracy must be greatly reduced, not least by slashing red tape preventing retired doctors and other healthcare workers from assisting the effort.

"But vitally, given the intense pressures on the NHS currently, if doctors and their colleagues, including those giving the vaccinations, are able to continue caring for patients they must be protected themselves.

"With warnings that the NHS could be overwhelmed in as little as three weeks, those risking their own health on the frontline must be vaccinated as soon as possible - and long before the middle of February - to enable services to cope."

The NHS is recruiting people to help with the distribution and has placed adverts in an attempt to recruit more people to help, but the numbers required are significant. Prof Shah said Imperial College estimates that 15,000 will be needed to reach a total of 250,000 vaccinations a day and double that for the half a million a day needed to exceed the two million doses that will likely be available.

If AstraZeneca is able to produce two million doses by the third week of January and Pfizer even more, a lack of qualified staff to carry out the distribution offers the prospect of doses sitting and waiting to be injected, with no one able to do the work.

4. Monitoring

As the vaccinations are dispensed, it will be essential to continue to monitor the distribution effort, to make sure it is being successful, which will also limit the speed at which it can progress.

This is especially critical as the government is pressing ahead with a plan to administer the first dose of the AstraZeneca vaccine to as many people as possible, before offering the second after 12 weeks - way beyond the 21 days that its efficacy was tested against.

The effectiveness of this will only become apparent if accurate and detailed records are kept of what happens to many of those who are given the alternative regime.

Conclusion

Experts say reaching the target could be possible, but it would depend on a whole series of actions being coordinated.

Prof Nilay Shah, head of department of chemical engineering, Imperial College London, said: "Our analysis indicates that at steady-state it would be possible, with a great deal of co-ordination of manufacturing, logistics, rapid training of vaccination administration personnel, co-operation of patients, it should be possible to reach daily vaccination levels of 300,000 to 500,000 doses per day.

"These levels are several times higher than those achieved in peak influenza vaccination but in principle are achievable with additional resources and effective co-ordination.

"At 400,000 doses per day, assuming we move to seven-days-a-week operation, that is 50 days, which would get us to mid-Feb (for 100% coverage). It's an ambitious target and needs everything to click every day.

"If the aim is for the first dose for the top four priority groups by mid-February, then we would need to hit 200,000 doses a day, again this is achievable but everything needs to go right every single day."