States were instructed on Jan. 12 to set aside second doses of vaccines and immediately begin vaccinating every American 65 and older, as well as those with medical conditions that put them at high risk of COVID-19-related mortality. I applaud this dramatic policy shift that has the potential to save lives. With multiple novel COVID-19 variants in circulation globally and more than 400,000 total COVID-19 deaths nationally, we must get as many people vaccinated as soon as possible.
Prior to Jan. 12, vaccine rollout required a primary shot followed by a booster either three (Pfizer’s) or four (Moderna’s) weeks later. These specific vaccination schedules resulted in the highly acclaimed 95 percent efficacy rates achieved in clinical trials.
In late December, the United Kingdom authorized the Oxford-AstraZeneca vaccine and prioritized the distribution of the first dose, delaying giving recipients a second dose by up to 12 weeks. The decision, UK health officials said, was to ensure more people are at least partially protected by one dose of the vaccine. By vaccinating twice as many people in the same amount of time, the UK strategy has the potential to prevent many deaths.
The United States’ adoption of a similar approach came without a moment to spare.
As of Jan. 23, the United States has given the first vaccine dose to approximately 6.4 percent of its population. On the other side of the world, the United Arab Emirates has vaccinated 23 percent of their population and aims to cover half of its population by the first quarter. Likewise, Israel has followed in a similar manner, vaccinating over 40 percent of people over the age of 60.
Importantly, the benefits of vaccine-induced protection extend well beyond those individuals vaccinated, as they also likely protect the greater community by slowing the virus’ spread. But the latter can only occur when more people receive the vaccine in the shortest amount of time.
Evidence shows that a single dose offers “robust” protection against disease about two weeks post-injection, but we must first acknowledge lack of certainty. There is supportive — but not conclusive — evidence that protection after one dose is as effective past the two-week window in which boosters were given in clinical trials. In both trials, once it was time to administer the booster, the primary shot was approximately 80 to 90 percent effective in preventing symptomatic COVID-19.
Vaccine policy makers naturally require definitive evidence to establish a standard practice. As the UK public health regulators understood, they wouldn’t be able to promise 95 percent protection to recipients of a single dose. There are also concerns that without an immediate booster dose, our protection will diminish rapidly.
We can’t achieve complete certainty now, but by closely characterizing the incidence and severity of COVID-19 infections occurring among those who are vaccinated, we should be able to answer these critical questions in real time as this new national policy is implemented. Close follow-up with vaccine recipients can be achieved with the “V-safe” post-vaccination health checking website.
In January alone, between 50,000 to 100,000 Americans could die of COVID-19. Over the coming weeks, let’s now characterize the pros and cons of expediting the first dose of vaccine to those in abject need. Prioritizing first doses of the vaccine was a critical decision, but likely a shrewd and effective one that will save many lives.
Guest writer Benjamin Sievers PZ ’22 is an EMT majoring in biology. He’s committed to putting diagnostic tests directly into our hands — starting with vulnerable populations, including those who are incarcerated.