By Brandi Greenberg, Vice President, Life Sciences and Ecosystem Research

Back in February, when U.S. vaccinations were picking up steam and our horrific winter Covid-19 surge was abating, I started speculating about when the pandemic might end. Admittedly, I focused my analysis narrowly on the United States, and I found plenty of reasons for optimism. My analysis led me to believe there was at least a 50% chance that the United States could achieve herd immunity—with 70-80% of the population immune through prior infection or vaccination—by summer, life largely returning back to "normal," and no major resurgence of disease next winter. I labeled this option the "good" scenario, while also acknowledging a "bad" scenario, where America doesn't achieve herd immunity until late 2021, and  a "worse" scenario, where vaccines falter and domestic herd immunity eludes us in 2021.

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Recent events, however, have caused me to question the core assumption underlying that prediction—namely, that national herd immunity is even the right goal. April's surges in Michigan, New Jersey, Brazil, and India made me realize that I've been looking at the pandemic through the wrong lens—a monolithic national lens. To answer the question, "when will life return to normal?" we must simultaneously acknowledge the persistence of local variation and global interdependency.

Regional US outbreaks are likely to persist throughout 2021

Despite phenomenal national, state, and regional efforts to collectively administer more than 200 million shots into American arms within Biden's first 100 days in office, daily vaccination rates are slowing, and many parts of the country now report that vaccine supply exceeds local demand. As of April 29, 43% of the U.S. population, or 143.9 million people, has received at least one vaccine dose, with approximately 30% of the population fully vaccinated. But vaccine uptake varies widely not only by state, but often by county and even by zip code. In my home state of California, for example, 49% of the residents in Marin County (a wealthy county just north of San Francisco) have been vaccinated. And that number surges to 79% among those over 65. Compare that to Kings County, located in a more rural part of central California, and that number plummets to 17% of all residents, and 46% of those over 65.

Digging deeper, I learned that this regional variation is about more than vaccine access or health literacy. According to Kaiser Family Foundation's Covid-19 Vaccine Monitor, 20% of those surveyed say that they still will "definitely not" get vaccinated or will only get a shot "if required." Among those who definitely won't get a shot (13%), they're twice as likely to live in rural areas vs. urban locales, and they're more than twice as likely to identify as Republican vs. Democrat or Independent. They're also more likely to believe or be unsure of common Covid-19 vaccine myths (e.g., contains live virus, causes infertility).

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I take away two things from this data. First, the next round of efforts to combat vaccine hesitancy (bordering on resistance) will be less about addressing access and medical mistrust, and more about countering medical misinformation and the unfortunate politicization of the pandemic. Second, rural "red" states and counties are going to have a harder time reaching herd immunity through vaccinations alone; it's also worth noting that these regions are also more likely to have fewer masking or social distancing requirements.

This fact—coupled with the reality that highly contagious variants (like B1.1.7) continue to spread in parts of the country faster than health care leaders can vaccinate the vulnerable—leads me to conclude that reginal outbreaks are likely to persist through at least the end of 2021. Taking us back to my original "good," "bad", "ugly" scenarios, unless health care leaders can make a meaningful dent in the share of Americans not yet ready or willing to get a Covid-19 vaccine, it's possible that highly immunized counties could experience a "good" Covid summer, while those in parts of the rural south or Great Plains with lower vaccination rates could see the "ugly" scenario play out.

Vaccine nationalism increases our collective risk that resistant variants will emerge across the globe

The most significant threat to any sustained regional or national "return to normal" lies not in those localized outbreaks but well beyond our national borders. To date, only 6% of the world's population has been vaccinated, leaving 7.3 billion people yet to receive a first dose. At this rate, it could take more than 4.6 years to achieve global herd immunity with two-dose vaccine regimens. Unless we can meaningfully compress that timeline, the rest of the world will serve as a giant petri dish for new Covid-19 variants. The virus will continue to mutate in ways that make it more transmissible and potentially more adept at evading antibodies from vaccination or prior infection.

Despite manufacturing commitments upwards of 14 billion vaccine doses by the year's end, inefficiencies in global production, purchasing, and distribution will ultimately send the vast majority of those shots to wealthier European and North American countries. In fact, according to Ivar Mendez, provincial head of surgery at the University of Saskatchewan, "ten of the richest countries in the world have really hoarded about 80% of the vaccines."

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COVAX (Covid-19 Vaccine Global Access) was set up specifically to ensure that its 92 participating middle- and low-income countries receive equitable access to vaccines. It's a global initiative led by the Global Vaccine Alliance (Gavi), Coalition for Epidemic Preparedness Innovations (CEPI), and the World Health Organization. The initiative secures doses through deals with vaccine manufacturers and participating high-income countries who "skim" 1-2% of their doses off the top to provide to the partnership. COVAX then disseminates those doses to its middle- and low-income participants for administration. In theory, it should work. So why have so few doses made it to places like Bolivia or Indonesia or sub-Saharan Africa? Why has it only delivered 38 million doses to its members, far short of its goal to distribute 100 million doses by end of March?

Certainly, a lack of manufacturing capacity and cold-chain distribution infrastructure contributes to the problem. But vaccine nationalism, particularly among wealthier Western nations, is also partly to blame. The United States alone has advanced purchase agreements for nearly four times as many doses as it needs to vaccinate its entire population. In mid-March, the U.S. sent a few million doses of Astra-Zeneca's vaccine (still not authorized in the United States) to Canada and Mexico. And a few days ago, the U.S. agreed to release up to 60 million more Astra-Zeneca doses to India and other countries around the globe.

That's a good start, but American leadership must do more, as must many other developed nations with manufacturing capacity or purchasing commitments in excess of local demand. We must also actively support global efforts to combat misinformation and reduce vaccine hesitancy, especially given the global outcry over rare blood clots from the two adenovirus-based vaccines that are much cheaper to produce and easier to distribute than either of the mRNA options.

It is in our collective national interest to help vaccinate the globe. While 2020 may have taught us all how to shelter in place, 2021 is reminding us that our path to anything resembling even local herd immunity or a return to normalcy is inseparable from global efforts to stop the spread and reduce the risk of dangerous Covid-19 variants.

Despite these barriers, I remain cautiously optimistic that the pandemic's worst days are behind us

As I noted earlier, 43% of our population has received at least one vaccine dose. Anyone over 16 who wants to get vaccinated can make an appointment and get a shot (understanding, of course, that access to technology and nearby administration sites remains challenging for some). Pfizer has requested an emergency use authorization (EUA) to administer its vaccine to teens ages 12-15, many of whom will likely get their shots this summer. Dark horse vaccine manufacturer Novavax recently released positive interim data from its own Phase III trial and may receive an EUA this summer, thereby expanding the number of vaccine options and total quantity of product available to help vaccinate the globe.

While the pace of vaccinations in the United States has slowed from a high of over 4 million per day to a steadier 2.7 million per day, maintaining that slower pace could still mean that upwards of 70% of Americans are vaccinated by mid-to-late summer. Local outbreaks remain likely, but many parts of the country are still on track to resume close-to-normal activity while managing a small but steady flow of positive cases.

Mounting real-world evidence continues to show that the vaccines dramatically reduce the risk of hospitalization or death from Covid-19. Nursing homes are reopening to visitors for the first time in over a year. Local restaurants are welcoming back guests. Delayed family celebrations are now taking place. There are plenty of reasons to remain hopeful.

What can health care leaders do to increase our chances of a 'good' outcome?

When I've written these predictions about the pandemic in the past, I struggled to see how my individual actions could meaningfully inflect our trajectory toward a good, bad, or ugly outcome. Ironically, as our national quest for herd immunity gives way to a patchwork of local battles and regional stories—and the clear impact of our nation's ability to send excesses vaccines across the globe starts to materialize—I feel much more empowered to make a difference. And you should, too. Whether you're a clinician, provider executive, manufacturer rep, or even just a concerned citizen—figure out one way you can improve vaccination rates or reduce the risk of spread in your own local community. Whether that is through improved messaging, establishing mobile vaccine clinics to reach vulnerable and rural populations, or simply getting vaccinated yourself, it all really matters at both the local and global level. It's a sobering picture, but one where the future is at least in our hands.  

Heather Bell, Pam Divack, Isis Monteiro, De Saulet, Thomas Seay, Darby Sullivan, and Paul Trigonoplos contributed to this piece.