You are using an outdated browser.
Please upgrade your browser
and improve your visit to our site.
Skip Navigation

“This Is Not a Silver Bullet for the Pandemic”

The promising results for two competing Covid-19 vaccines are raising hopes, but experts warn that there are still unprecedented challenges ahead.

Joe Raedle/Getty Images
A vaccine study in Florida

Last week, Pfizer and BioNTech announced that their vaccine is more than 90 percent effective at preventing Covid-19, which was followed on Monday by Moderna declaring that its vaccine is 94.5 percent effective at preventing symptomatic cases and seems to reduce the severity of cases. Although experts heralded the promising results, they also cautioned that developing effective vaccines is just one part of the picture. After these vaccines are ready for the public—which will take months—the next stage will be rolling them out and getting people to take them. It will be a massive undertaking to build up health care infrastructure alongside one of the largest-ever public information campaigns.

The most obvious challenge when it comes to vaccine distribution is storage. The Pfizer-BioNTech vaccine needs to be kept at minus 94 degrees Fahrenheit, a lower temperature than most medical freezers can reach, which would necessitate the development of a new cold chain to get it to patients. On that front, Moderna had good news: The company announced that its vaccine can be stored at minus 4 degrees for six months, and it lasts in a standard refrigerator (at 36 to 46 degrees) for up to 30 days. That would make getting it into doctors’ offices and pharmacies much easier.

But experts say refrigeration is just one challenge to getting the vaccine into the arms of those who need it.

“It makes really good headlines—oh, yeah, 90 percent effectiveness. But then there are actual challenges to implementing it,” Dr. Bijay Acharya, a hospitalist in Baltimore, told me. How can the vaccines be kept cold enough as they are shipped across the country and stored in hospitals and doctors’ offices? If doses begin expiring soon after they are thawed out, how can they be given to patients quickly without going to waste? “The way we do vaccinations is not clear,” Acharya said.

In fact, we have never seen a vaccination campaign on this scale for adults anywhere in the world. “Most of the global immunization programs focus on getting basic shots to kids zero through five years old—not to adult populations,” Jamie Bay Nishi, director of the Global Health Technologies Coalition, told me. In some parts of the world, there aren’t even campaigns to give adults flu shots every year. Figuring out how to deliver a vaccine to adults will be a challenge, she said.

There are other logistical questions, as well, from how millions of vaccines will be delivered across the country to who will administer them and where. And even if the vaccines don’t require ultracold storage, there will still be limitations on how many regular freezers and refrigerators are available for vaccination campaigns. “Cold chain is going to be a huge issue, both here in the United States and globally,” Bay Nishi said.

Few vaccines in the U.S. are frozen. Pharmacies and grocery stores usually use refrigerators to store vaccines, and many of the existing vaccine freezers found in pediatricians’ offices or hospitals typically max out around 40 degrees below zero. Facilities that do have minus–90 degree freezers are probably already using them for something else. This type of ultrafreezing is usually used to preserve tissue samples and frozen embryos, but it hasn’t really been used to store vaccines before.

The fact that brand-new vaccines against a new virus will require new distribution strategies isn’t that surprising, Ross Silverman, a professor of health policy and management at Indiana University’s Fairbanks School of Public Health, told me. “But the systems that have been created to deliver vaccines weren’t created with this type of vaccine in circulation, so we’re up against a number of structural challenges.” Pfizer and BioNTech plan to send their vaccine in batches of 1,000 doses—in rural areas, it may be hard to administer that many doses to the small or scattered population before the vaccine expires due to not being kept cold enough.

And while the pandemic has exposed and heightened worldwide inequalities, a vaccine could also deepen the divide between the rich and the poor, at least initially. Wealthy areas may receive batches of the vaccine first simply because they have the facilities to store them. That could mean that rural areas of the U.S., which are currently experiencing the worst of the pandemic, might never see the supercold vaccines at all. If the vaccines that are easier to store are less effective, it could perpetuate inequities, a major concern of many of the experts I spoke to.

Another challenge: Nearly all of the vaccines in late stages of development require two doses, a few weeks apart, to work well. “How do I make sure that I’m getting inoculated with the same vaccine’s part two, and not a different one that might mess up the regimen?” Bay Nishi asked. Careful tracking of who got which vaccine, and when, will be required, which can be difficult in countries like the U.S. with no centralized health-records system.

Once the Pfizer-BioNTech vaccine is developed, the vaccine makers will likely experiment with how cold exactly it needs to be, Bay Nishi said. They could work backward to improve thermostability, or the ability to withstand higher temperatures, once the vaccine passes regulatory hurdles. “The first-line vaccines are not necessarily going to be the best,” she said. “It may be that the second line of Covid vaccines are the ones that are really going to be ultimately better.” In addition to being more stable at higher temperatures, the second round of shots could be more effective, especially with a single dose.

But then there’s the issue of getting people to get the shots once they’re available. “I worry we get the freezer, we get [the vaccine] all the way to the patients’ community, and people are hesitant to take it,” Acharya said.

Dr. Angela Rasmussen, a virologist and affiliate of the Georgetown Center for Global Health Science and Security, is also concerned about vaccine hesitancy, a term for public worries about vaccine safety and efficacy. “Long term—and this is true of all the vaccine candidates—there’s going to be a pretty steep hill to climb in terms of convincing people to actually get it,” she told me. “When we get a vaccine, it’s going to be the beginning of the end. But the end itself will take months—potentially years, if it takes a long time to convince people to actually get it.” An important part of overcoming hesitancy will be transparency about how the vaccine works and what it does—and doesn’t do.

Both the Moderna and Pfizer-BioNTech clinical trials measured how many symptomatic Covid-19 cases were reported after immunization with the shots or with a placebo. But it’s not clear whether they’re seeing asymptomatic cases—and, if so, if those asymptomatic people are still contagious. “If it’s protecting people from severe disease but they’re still getting infected, we need to find out how much virus they’re shedding, and whether or not they’re a transmission risk for people who have not been vaccinated,” Rasmussen said.

The continued politicization of the pandemic, and the Trump administration’s role in spreading misinformation and disinformation, could derail these efforts, she said. “Given that Donald Trump is the kind of person that, if he can’t have a toy, he’s going to break it so that nobody else can play with it—I don’t think that should be underestimated.” That being said, the processes for evaluating the safety and efficacy of the vaccines, and the rollout of approved vaccines, are already underway. “The question, I guess, is how much Trump is going to actively interfere with any of those processes. And I don’t think that’s anything we can really predict,” Rasmussen said.

Others question the Trump administration’s decision to invest significant sums in vaccines and therapeutics that may work without investing in what already works: personal protective equipment, contact tracing, testing, and providing income and housing support to those who test positive. “There was a guarantee that they would buy almost $2 billion worth of vaccines,” Acharya said. “We still haven’t heard the government saying it’ll buy $2 billion worth of PPE.” Instead, he said, many doctors, nurses, specialists, and cleaning staff are scouring online stores and Home Depot for masks, on their own dime, because they face shortages at work.

“I think my biggest fear is, it’ll sway the public opinion or the policy and the resources toward investing in vaccinations,” he said. “And this PPE [shortage], the burnout the nurses and staff are facing, the mental health trauma that everyone is facing … that’ll just be forgotten because now you have this extremely positive news—which is important, but also, at the same time, we’re not investing in testing, we’re not investing in contract tracing.”

Experts also caution against seeing the vaccine as a magical end to the pandemic. “This is not a silver bullet for the pandemic,” Silverman said. “We’re seeing exponential rise in the number of cases; we’re seeing hospitals getting not only overwhelmed but also cutting back on the elective procedures again, which means that their economic situation is more vulnerable.”

“This is going to require ongoing support. As we turn to 2021, everybody’s going to have to start thinking about the next state and local public health budgets,” Silverman said. So far, states and cities have received only a fraction of the government’s funding for vaccines. Yet this needs to be a global effort, Bay Nishi adds. “We’re not going to be safe from Covid-19 anywhere until we are safe from it everywhere.”