In a welcome break from increasingly grim news about the pandemic, Pfizer reported encouraging results last week (and Moderna this week) from their COVID-19 vaccine trials. But the path to vaccine-based protection will require more than just the science working in our favor. As public health experts like to say: Vaccines do not save lives; vaccination saves lives. Distributing and delivering are enormous challenges that will determine the speed and strength of our recovery.

It will take well into 2021 before enough vaccine is ready for everyone. Even before we reach that point, we will have to overcome a wide array of challenges. Among them, we can count moving and storing a vaccine that must be continuously kept at freezing temperatures; identifying and locating groups of individuals who have been chosen for priority access on the basis of their risk or employment; tracking every dose to monitor for safety and uptake; and communicating about vaccine safety and effectiveness. And, finally, after sufficient quantities of vaccine finally become available, we will need far-reaching campaigns to actually vaccinate many people as quickly as possible.

The Trump administration has said that the military will play an important role in distributing the vaccine, and Army personnel and vehicles may be useful in transporting vaccines and providing logistical support. But make no mistake: The critical work — at almost all levels in the process, from the initial logistics to the actual work of vaccination — must involve state and local health departments. If they're going to succeed, they'll need to inspire confidence in the vaccination process and reach populations most at risk for serious illness and death from COVID-19. And if they're going to do that, they're going to need resources that they're not currently receiving.

To date, states have received only $200 million from the federal government to help them plan to distribute vaccines, which is nowhere near enough to meet the most urgent needs. The Association of State and Territorial Health Officials and Association of Immunization Managers estimate states and localities will need $3 billion to hire and train outreach workers, as well as $500 million to support communications and engagement. This and other necessary funding had been included in recent stimulus proposals but has not yet passed Congress. The amount that has been distributed thus far is tiny compared with the more than $10 billion the U.S. government has already spent in supporting the development of vaccines, let alone the trillions of dollars of economic harm that the novel coronavirus is causing the economy.

Health officials across the country must explain the vaccination process to those who are eligible to receive the first doses, as well as to the broader public. Over time, vaccines from multiple companies may ultimately be used, which will require nuanced messages about the attributes of each.

These new generation vaccines, made of RNA, require an ultracold supply chain and involve giving two doses, one month apart. Moving, storing and administering these vaccines will require special freezers, and every dose will have to be tracked for ongoing monitoring of safety.

Arguably the most important task of health departments is to locate and serve communities and populations at the highest risk. To date, African Americans, Latinos and Indigenous people are dying of COVID-19 at more than three times the rate of White Americans, adjusted for age. Without an investment to reach those who are not easily able to access health services, the shocking racial and ethnic disparities in COVID-19 mortality may only get worse.

To close these gaps for COVID-19, state and local health departments must work with trusted leaders to communicate about the safety and importance of vaccination. With the ability to hire community health workers and other staff and set up on-site vaccination clinics, health departments can deliver and administer vaccines in low-income senior housing developments and even set up mobile vaccine clinics inside communities that lack ready access to clinics and pharmacies.

Health departments will need major investments in staff and supplies. Without new funds, the best plans will lie on the shelf. Vaccines will fail to reach many at greatest risk. And the pandemic will continue to claim far too many lives.

Jennifer B. Nuzzo is a senior fellow for global health at the Council on Foreign Relations and an associate professor at the Johns Hopkins Bloomberg School of Public Health. Joshua M. Sharfstein is a professor at Johns Hopkins and previously served as secretary of the Maryland Department of Health and Mental Hygiene.