How will Covid-19 vaccine be rolled out and who will get it first?
Posted on November 10th, 2020

Rhys Blakely, Science Correspondent Chris Smyth, Whitehall Editor |Kat Lay, Health Editor Courtesy The Times

Vaccine developed by Pfizer and Biontech could be approved for use as early as next month. Getting it to clinics and into the arms of the British population will be one of the biggest challenges faced by a peacetime government.

The vaccine appears to be highly effective at preventing symptomatic Covid but is unstable at anything but ultra-low temperatures. The technology has never been used at scale and will require a supply chain unlike anything used before.

GPs have been asked to contribute to an ‘all hands to the pump” effort to administer the jab — but experts have doubts over whether primary care clinics can cope. Mass vaccination centres are planned, preparations are being made to take the vaccine to care homes and the military is standing by to assist. The scientists have done their bit, now they pass the baton to the NHS.

The factory
Britain’s doses will come from a factory in Puurs in Belgium, where the manufacturing process will have begun with a snippet of DNA.

This will have been used as a kind of template to synthesize billions of copies of a second type of genetic material known as mRNA, the messenger molecules at the heart of the Pfizer vaccine. Once injected into a person, they instruct cells to produce the coronavirus’s famous spike protein”. This trains the immune system in how to fend off the real pathogen.

An advantage of using mRNA is that a little goes a very long way. A one-litre flask might contain enough raw material for tens of millions of doses. First, however, it must be purified and then encased in microscopic fatty capsules.

This is where things get complicated. At room temperature, these capsules will clump together, rendering the vaccine useless. To prevent this, it must be kept in ultra-cold conditions.

This morning John Bell, regius professor of medicine at Oxford University, spelt out the stakes to MPs. The vaccine needs to be stored at minus 70C, according to Pfizer.

The idea that that’ll be done through local GPs sounds a bit unlikely to me,” he told a joint hearing of the health and social care and science and technology select committees. A bespoke solution” was required, he said.

He put the chances of vaccinating the most vulnerable parts of the population by Easter at 70-80 per cent, provided they don’t screw up the distribution”.

The supply chain
Pfizer has created two distribution hubs. A plant in Kalamazoo in Michigan will serve America while Britain’s supplies will come from Belgium. Each facility has hundreds of large ultra-cold freezers, ready to store millions of doses before they can be shipped around the world.

Pfizer wants to deliver as many as 100 million doses this year, with up to ten million going to the UK. It aims to produce another 1.3 billion in 2021. Each person will require two shots, separated by three weeks; protection against Covid should develop a month after the first injection.

It’s the biggest vaccination campaign in history,” Tanya Alcorn, Pfizer’s vice-president of supply chain, said.

In the US the company plans to use cargo space on an average of 20 flights every 24 hours and a similar timetable is expected in Europe. Pfizer has a goal of getting doses to the point of use in no more than 72 hours.

When they reach the UK, however, responsibility will be handed over to the NHS.

The final miles
When they arrive in Britain, the vaccines will be in special suitcase-sized containers capable of keeping them at minus 70C for up to ten days, if the outside temperature is not above 25C and the box is not opened. This means refrigerated trucks will not be needed. Each container is designed to hold between 1,000 and 5,000 doses. They will be packed with dry ice and they have a GPS system to track their location and a thermal sensor.

The rules on how they can be handled are demanding and still evolving. After Pfizer hands them over, they must be repacked with fresh dry-ice within 24 hours. After that, they can only be opened for a minute at a time. Pfizer told US officials in August that they should not be opened more than twice a day, though this may change.

Once defrosted, the doses can be held in a standard refrigerator, at between 2C and 8C. Exactly how long they can be stored like this is unclear. In a document prepared for US officials during the summer, Pfizer originally spelt out a 24-hour limit. There are signs that this could be increased, with a spokeswoman for the company saying today that the vaccine has an effective life of up to five days” when stored at temperatures of 2-8C.

She added: We seek to work with governments to support distribution to their defined priority groups, and we anticipate that points of vaccination will vary around the globe but may include: hospitals; outpatient clinics; community vaccination locations and pharmacies.”

At room temperature they will last only a couple of hours.

Where will the vaccines be given?
The government has plans to train an army of workers, including physiotherapists, paramedics and midwives, to administer Covid jabs. Matt Hancock today outlined several routes of delivery. Large vaccination centres would be set up, he said. These could include sports halls and car parks.

The vaccines will also be taken to care homes, whose residents and staff will be a top priority.

GPs were also issued instructions in a letter from NHS England. They were told to work in groups of practices called primary care networks, designating one site in each area to host a vaccine programme between 8am and 8pm, seven days a week including bank holidays”, raising the possibility of vaccinations on Christmas Day.

Each site should plan on delivering a minimum 975 doses a week and with 1,250 such networks that amounts to capacity for at least 1.2 million doses a week. At this rate it would take about five months to vaccinate everyone over 65.

The letter asks GPs to recognise that running a potential Covid-19 vaccination programme requires ‘all hands to the pump’ and pragmatism”. But GP and health leaders have warned that this could mean significant disruption to other routine services, with the NHS Confederation saying: Delivery of a vaccination programme on this scale from scratch means business as usual is not feasible so public expectations will need to be managed.”

GPs were also told to assume that they will need to leave at least seven days between flu and Covid vaccines. Specifications for vaccination sites do not mention freezer space, only the need for refrigeration, possibly suggesting that each site will be supplied daily.

Who will be vaccinated first?
Boris Johnson said yesterday that decisions on who would be prioritised were yet to be finalised. The final order will depend on how effective the inoculation is in older people, which is not yet known. The Oxford vaccine might become available early next year, which could provide more logistical flexibility.

At present, the joint committee on vaccination and immunisation has a provision plan which calls for older people in care homes and care home workers to be vaccinated first. Next come all those 80-plus and health and social care workers.

There then comes a tier system of age groups: all those 75 and older, then all those 65 and older. High-risk adults under 65 come next, followed by moderate-risk adults under 65. Then all those 60 and older; those 55 and older; those 50 and older. Finally comes the rest of the population.

Whether young fit adults and children would be vaccinated is unclear. Some experts feel that the risks of using a new vaccine on these groups may outweigh the risks of catching Covid. Without them, however, herd immunity — where enough of the population is protected to prevent the explosive growth of new outbreaks — would probably not be achieved.

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