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Anticipation of a covid-19 vaccine is growing. The National Academy of Medicine issued the report “Framework for Equitable Allocation of Covid-19 Vaccine,” offering guidance on vaccine allocation. The process is certain to be fraught with politics, given that equitable, safe and effective all represent critical, albeit subjective criteria to assess the vaccine allocation process and meet the requirements of the vaccine supply chain.
Multiple manufacturers will provide vaccines, and they are certain not to be interchangeable. Each vaccine will come with its own set of adverse side effects, dose requirements, temperature requirements and effectiveness metrics. This has the potential to make the vaccine allocation and distribution supply chain highly complex and rifewith uncertainty. With multiple criteria needed to evaluate this process, there will be no one-size-fits-all solution.
To illustrate one such complexity, the FDA considers a 50% threshold for vaccine effectiveness as desirable across the entire population. At the same time, for some vaccines, effectiveness wanes with the age of the recipient. However, the virulence of covid-19 increases with age, which means that the people most at risk with covid-19 may also be the people for whom the vaccine may be least effective. This adds a wrinkle of uncertainty into the tradeoffs between equitable, safety, and effectiveness.
Evaluating any public good is fraught with bias and politics. Objectively, to squelch the spread of the virus means that those who occupy roles on the most active virus transmission highways must be a top priority. This includes health care workers and those in essential services. Such people serve critical roles for the functioning of our nation, and as such should be at the head of the line for any vaccines.
As is the case for the delivery of medical countermeasures, the last mile is frequently the longest to traverse. Our nation has a logistics system in place to move vaccines, like those for pediatric diseases and seasonal influenza, from manufacturers to distribution centers to health care providers. The challenge is getting the vaccine into the arms of all who need and want it. Congestion at primary health care facilities may quickly overwhelm the system. Pharmacies and faith-based organization may buffer some of this last-mile delivery surge.
Depending on the timing of its availability, vaccine distribution may collide with the 200 million doses of seasonal influenza vaccine that will be available in the fall of 2021. Based on overlaps between the manufacturers of the covid-19 and the seasonal influenza vaccines, it may be possible to use a common distribution network for both, simultaneously easing the logistics highway. The big unknown is if such vaccines can be administered simultaneously, which if they cannot, may add to the logistics distribution turmoil.
An issue that has drawn attention is that a sizable number of people have indicated no interest in taking the vaccine or prefer not to be in the first wave of those vaccinated. This will naturally reduce the demand for the vaccine and make it easier to allocate the vaccine to those who want it. By knowing the general location of initial demand, via a web interface and app, distribution networks can be planned in advance. With reduced demand for the covid-19 vaccine, the logistics of distribution and delivery may be more manageable than decision-makers anticipate, easing the inherent conflicts between equitable, safe and effective.
Trying to proactively define the allocation order for covid-19 vaccination before it is even clear the type of vaccines that will be available is certain to create more chaos than calm. Human nature is such that perceived shortages of items creates demand surges beyond available capacity. We experienced this back in March and April 2020 with toilet paper and cleaning solution shortages. Recall the confusion surrounding the distribution of the H1N1 swine flu vaccine back in 2009.
If covid-19 vaccines only become available in the second half of 2021, and the trend of confirmed cases continues on its current trajectory, the United States will hit 20 million cases by late summer 2021. If the CDC’s analysis is correct, that for every confirmed case there may be five to 10 more unconfirmed infections, then 30% to 60% of the population will have been exposed. This may naturally slow the spread of the virus, which means that a vaccine will provide the greatest value earlier rather than later in the virus’ progression through the population. Unfortunately, history suggests that it will take years, not months, for a safe and effective vaccine to be developed. Will this make such vaccines “too little too late” to prevent many more excess deaths?
Clearly, the road to a covid-19 vaccine still has many hurdles. With some sensible planning and data collection, the covid-19 vaccination supply chain, whenever it is activated, may be less daunting than many expect.
Sheldon Jacobson is Founder Professor of Computer Science and director of the Simulation and Optimization Laboratory and the Bed Time Research Institute at the University of Illinois.
Coronavirus | Featured Commentary | Opinion