The good news this week was that the US Food and Drug Administration (FDA) issued emergency use authorisation for the Pfizer-BioNTech vaccine. The FDA has also declared that the Moderna vaccine is safe and 94% effective, paving the way for its authorization too. 

The Centers for Disease Control and Prevention (CDC) prioritized healthcare workers and nursing home residents and staff as the vaccine’s first recipients. But once the vaccines are available in larger numbers, as will soon happen, we desperately need a plan for how to effectively roll them out across the country. Otherwise, we risk undermining confidence in the vaccines and adding uncertainty about the role of vaccines in the covid-19 response. 

That plan starts with defining a national vaccination strategy, which so far hasn’t happened. As a result, there is currently widespread confusion about whether the aim of the roll-out is to prioritise and protect the individual being vaccinated, or to build up immunity in the larger community to slow the spread of the virus—or both. Deciding which approach to take and explaining it to the public is vital because it impacts every aspect of how we go about distributing the vaccines.

Usually, public health officials set objectives or targets for vaccination coverage at the outset. In vaccinating against measles, for example, the aim has been to get at least 90 percent of children vaccinated because research shows that is the threshold required to stop transmission. While individuals are personally protected by getting their measles shots, the ultimate goal is community protection, which only comes when population coverage levels are high. 

But community protection is not always the objective of vaccination. Some vaccine efforts prioritize vaccinating individuals who are at risk against specific diseases, like tetanus. For flu, the aim is both community and individual protection, which is why hospital workers, nursing homes and other places where community transmission could be deadly are prioritized. 

The lack of clarity on a strategic approach to covid-19 vaccination is already setting unrealistic expectations among the public, which undermines public trust. At the moment, most Americans seem to believe we will all start getting vaccinated and simply get back to normal life. In other words, most Americans are expecting vaccination to create a herd immunity that will sufficiently protect the community to resume their pre-covid lives. The CDC has whispered that mask wearing and social distancing will need to continue even after millions of Americans are vaccinated, but it hasn’t started explaining to the public why this is the case.

Unfortunately, a herd immunity approach to reach the threshold required to completely suppress transmission of coronavirus will be near impossible in the coming year because it requires vaccination of children. Since trials in children are only just beginning, young people will likely not be vaccinated for the foreseeable future. And as that demographic makes up nearly 25 percent of the US population, a herd immunity strategy based on vaccination in the near term is unlikely. The only human disease in history to have been successfully eliminated is smallpox—and its eradication required both an effective vaccine and a coordinated worldwide effort based on a clear strategy.  

While our coronavirus vaccination strategy may change with confirmation that new vaccines are safe and effective in children, for now the strategy will need to prioritise reducing mortality of individuals in high-risk groups and transmission in high-risk settings.

Even with a clearly defined strategy in place, vaccinating hundreds of millions of Americans will not be easy. For starters, the current front-runner vaccine candidates are very different from one another, and the ways they are delivered are not interchangeable. The Pfizer vaccine, for example, relies on ultra-cold refrigeration, which requires special equipment that most pharmacies and clinics don’t possess. It is also delivered in multi-dose vials, rather than a single-dose, pre-filled syringe, and must be divided into individual injections, which requires additional preparation. Unlike flu jabs, the covid-19 vaccines available so far are two doses and the interval between each dose depends on the specific vaccine. 

A number of states have said that they plan to use a campaign approach based at mass distribution sites, such as gyms and convention centers, and mobile clinics. From an organisational standpoint, this resembles a medical version of early voting or a blood donation drive and is extremely challenging to do well. People must wait in line and follow directions, there is paperwork to make sure each person who gets the vaccine is properly tracked and comes for their second dose, the vaccine must be kept in the correct cold storage conditions, and the people delivering the vaccine must be properly trained and protected with personal protective equipment.  

While vaccine campaigns are frequently conducted in low-income countries, there is no recent precedent for such campaigns in the US. They can completely derail normal healthcare services because of the massive people power required to conduct them. It would be considerably better to use primary healthcare services and not set up a parallel delivery system.  

While US pharmacies have helped provide greater access for flu vaccines, there is no experience of delivering vaccines that need extreme cold storage or multi-dose vial preparation in retail outlets.

We know that covid-19 is not an equal opportunity killer. Those hit hardest are older people and people with underlying health conditions, many of which are driven by social determinants including race, economic status and lack of access to healthcare. In part, this means that the vaccination strategy will have to aim specifically at reaching these vulnerable populations—going directly to them—and not waiting for them to come to a vaccination site. 

To really address the high covid-19 death rates in the medium to long term, the incoming Biden administration will need to enact a parallel commitment to universal health coverage to help protect those people vulnerable to underlying conditions, like diabetes and heart disease, that put them at risk of severe covid-19 disease in the first place.  

Any vaccination campaign relies on trust. What we have learned from decades of experience with measles, polio, and other infectious diseases is that building trust requires public health officials to work with communities to devise a plan that addresses their fears, and engages them to figure out the logistical challenges. 

As the federal government and state and local authorities roll out covid-19 vaccines, they must be clear about what they want to achieve. At this point, there is a long road between emergency use authorisation and reaching population immunity. Vaccines don’t deliver themselves. They require a safe, trusted and accessible immunisation system. It is time to face up to that reality and set clear public expectations for the year ahead. 

Nina Schwalbe is a Principal Visiting Fellow at the United Nations University International Institute of Global Health and  an adjunct professor in the Heilbrunn Department of Population and Family Health at the Columbia University Mailman School of Public Health.

Competing interests: None declared