If the Pfizer-BioNTech vaccine gains regulatory approval by Christmas, we can cheer the scientists for heroic work. But it will be the distribution decisions made by governments that will determine how quickly we can all exit Covid confinement. The UK has put itself in a strong position to access early vaccines, but its approach to prioritization and distribution needs careful thought.
The UK’s National Vaccine Taskforce spread its bets early on, putting in orders for 340 million vaccine doses among six different vaccine candidates. Pfizer’s vaccine is one of them and Britain should be an early beneficiary, receiving a total of 40 million doses of the vaccine and possibly a portion of that before Christmas. Given the double-dose requirement for efficacy, that means 20 million Britons can be vaccinated.
That’s great news, but the corollary is that there has to be rationing. The UK health-care system has experience with that, of course. The country’s National Institute for Healthcare Excellence (NICE) evaluates medicines and treatments and sets up protocols for determining who gets what.
How to ration a vaccine, though? The UK’s vaccination strategy, first published in the Lancet late last month, sets out tiers of prioritization, starting with getting the vaccine to the very old and to those working in care homes before moving down the age brackets. Prioritizing the most vulnerable members of society is a common approach. Germany’s strategy is to vaccinate at-risk groups first, along with nurses and doctors. An estimated 40% of the population gets first dibs on a vaccine under the German plan.
But what if vaccinating the elderly first isn’t the best way to minimize fatalities? A recently published (but not yet peer-reviewed) model from three academics at Khalifa University suggests priority should be accorded to groups with the highest number of daily in-person interactions, since that amplifies the vaccine’s effectiveness by reducing infections (and mortality) both among the vaccinated group and those they come into contact with. According to their model, proper prioritization can reduce total fatalities by up to 70%.
If we get more immunity bang for each vaccine dose by targeting those with the highest number of interactions, then we’d want to see health-care workers at the front of the queue, but perhaps next in line should be younger workers and those in the hospitality sector. Perhaps children should be high up on the list too. Even though they seem to be the least impacted by the disease, they can have many daily interactions, especially with schools open.
A similar case is sometimes made with respect to seasonal flu vaccination programs. Younger populations are less likely to suffer severely from the flu but more likely to pass it on to those who will. And flu deaths don’t seem to be decline significantly from vaccination programs just targeted at the elderly. Following this logic, a number of countries (Finland, Latvia, Slovakia and the UK among them) have encouraged flu vaccinations of children to prevent broader transmission.
There are other ethical considerations. Because trials do not include a proportional share of the population who are most at-risk of dying from the disease, the efficacy (and safety) of a vaccine among this group is harder to establish. Vaccinating younger people earlier and faster — even offering financial inducements for it — would help amass more data on the vaccine while also potentially reducing the spread in the population.
Of course, any unknown safety risk may be worth taking to protect the elderly (given three-quarters of deaths are in the over-65 age group) and the immunocompromised. But whatever its calculations, the government needs to be transparent about its models and the assumptions they contain; so far that information has been lacking.
The success of any early vaccination program with limited supply also depends on how effectively the available doses can be deployed. In Germany, 60 vaccination centers are being established nationwide and the Bundeswehr (Germany’s military) is involved in the logistics. Medical workers will be trained on how to store the vaccine and administer it properly. (That’s no easy feat as the Pfizer vaccine must be transported at the ultra-cold temperature of -70 degrees Celsius, or -94 Fahrenheit.) Germany is also setting up a database to keep track of which population groups have been vaccinated, and with which vaccine and specific batch, to aid a broader program.
The UK’s publicly disclosed plans are more vague. It is also talking about creating mass vaccination sites, but the vaccine would also be distributed through doctors’ offices and hospitals. Health Secretary Matt Hancock has allocated an additional 150 million pounds ($199 million) to support the effort. But it’s easy to worry about whether this rollout will work as planned. Having many points of distribution will make the vaccine easier to access, but it also raises the risk that doses will be corrupted through incorrect storage or that those who are not eligible will receive it. Theft might even be a concern.
The supply constraints should start to ease sometime next year. Pfizer hopes to make its vaccine available in a more transportable powder form. And by the end of 2021, the expectation is that more vaccines that are easier to store should also become available. The more approved vaccines there are, the more sweeping programs can be. The UK strategy also wisely includes therapeutics, such as an antibody cocktail in development from AstraZeneca, that could be useful in cases where people can’t receive a vaccine (such as those who are severely immunosuppressed).
This week brought good vaccine news, but the next steps must be carefully planned. We are still far from the point when a vaccine will be available to all. Until then, prioritization and distribution are key. The scientists who brought us the Pfizer vaccine have shown us the exit door. It’s now up to governments to get people through it.
Bloomberg
