COVID 19

Christmas has come early, as over the last month good news keeps rolling in; the Pfizer, Moderna, Oxford, and the Russian based Sputnik vaccines have all shown high-effectiveness in at least preventing acute symptoms of Covid-19, but how do they compare to each other?

Ed Brown

News, 27 November 2020
 

The Pfizer/BioNTech and Moderna vaccine have been found to have 95% effective with two full doses, the Sputnik as well with a, although debated, 95% effectiveness, while the Oxford AstraZeneca vaccine was found to be 70% effective with two full doses, and possibly has an increased 90% effectiveness with a half dose and then a later full dose.

Although it is mentionable that during the Oxford vaccine trial none of the participants developed severe symptoms even if they caught the virus and consequentially did not required hospitalisation; therefore even with the 70% effectiveness, it may be viewed as a success.

So, there are good reasons to feel optimistic about 2021. Nevertheless, maybe it is naïve to think that Covid-19 will be over by the spring, as Pfizer, Moderna, and AstraZeneca will not be able to deliver enough doses to meet global demand. Moderna aims to produce 500 million to 1 billion doses, AstraZeneca aims to produce 3 billion, and Pfizer aims to produce 1.3 billion doses by the end of 2021, enough to collectively immunise up to approximately 3 billion people – under half of the world’s population if the Oxford vaccine is useful with the half dose approach.

The UK Government has pre-ordered 100 million doses of the Oxford vaccine, 40 million of the Pfizer vaccine, and 5 million doses of the Moderna vaccine – enough to immunise the whole population by the end of next year, if regulators approve these vaccines and supply can keep up with the overwhelming demand.

How will the UK public get vaccinated? And how much will it cost?

How any vaccine is to be rolled out in the UK was outlined in September, in an 11 staged approach that was developed by the Joint Committee for Vaccination and Immunisation, beginning with those working and living in care homes, and rolling down until those aged 50 and older, and then finally unto the rest of the population. Although, before 60-year-olds are vaccinated, younger high and moderate risk, individuals are to be prioritised.

Plans are yet to be finalised as to where the public will be able to get vaccinated. However, a proposal like that of the yearly flu vaccination programme has been suggested, that involves care home and residential visits by medical professionals, and the utilisation of GP surgeries. This will be a mammoth effort as the vaccines will be twice administered with just under a month between each one, therefore requiring double the work.

In terms of price the Pfizer, Moderna, and Oxford vaccines differ widely – the Pfizer vaccine costs £29.26 for the two doses, Moderna’s costs £37.5-£55.52 for the full course, and the Oxford vaccine approximately £4.50 if the vaccine is useful with the half and full dose. Although, any vaccination project will also involve considerably more cost to the public purse than merely the vaccine alone, due to the immeasurable logistics of getting out the vaccine as fast as possible, e.g. retaining or recruiting more medical professionals to keep up with the almost never-ending workload.

The reason that the Oxford vaccine is comparably cheap is because of prior commitments that the vaccine will be non-for-profit in developed countries until the pandemic is over, but also that it will remain non-for-profit in developing countries – so the price may increase in the UK when the pandemic is defined as ‘over’.

How will the world get vaccinated?

Getting any vaccine out to the four corners of the globe will be a logistical challenge – especially for isolated communities, and ones who live through rugged or otherwise difficult terrain. Furthermore, each of the prospective vaccines has requirements to make them viable – all of them necessitate cooled storage, although to different degrees.

The Pfizer jab has to be stored at -70C, much lower than the average home freezer, and cannot be removed from this state more than four times. At the conclusion of phase 3 of their study, Pfizer acknowledged this by mentioned that: ‘challenges related to our vaccine candidate’s ultra-low temperature formulation and attendant storage, distribution and administration requirements.’

Moderna expects that their vaccine can be maintained in temperature of -20% for long-term shipping and storage, the average temperature of most home or medical freezers, and after thawing it is expected that the vaccine will be able to be maintained at a standard refrigeration temperature for up to 30 days.

Logistically, the Oxford vaccine is suitable to rapid and diverse deployment, as it can be stored at refrigeration temperatures making it perfect for shipping and longer-term storage. Dr Michael Head, Senior Research Fellow in Global Health, University of Southampton, said: “This vaccine candidate …requires refrigeration storage rather than the ultra-low temperatures of the Pfizer candidate. Oxford have previously confirmed that there would be some level of distribution to low-and-middle-income countries so this may also be good news around the subject of equitable access to vaccine development with a product that is much easier to store and distribute.”

Whilst the pandemic is far from over, and all announced candidates remain potentials in the race, but the rapid production of these vaccines have been no small feat and should be celebrated, especially as three of the most recent pandemics – SARS, HIV, and Spanish Flu – were never solved with a vaccine. Ultimately what we can gather is that collective effort has achieved the hope that 2021 will be a better year than the last.