Public health officials, saying that the COVID-19 vaccine supply now exceeds demand from healthcare workers and long-term care residents the first 1a immunization priority groups are opening up vaccine eligibility to a broad swath of society. This includes those 65 years of age and older and those under age 65 years with high-risk medical conditions.

The Pfizer vaccine can be given to those as young as 16 years of age, while the Moderna vaccine is approved for those age 18 years and older.

“Every vaccine dose that is sitting in a warehouse rather than going into an arm could mean one more life lost or one more hospital bed occupied,” Alexander Azar Jr., secretary of Health and Human Services (HHS), said at a Jan. 12, 2020, press conference. “We are expanding the groups getting vaccinated because state restrictions on eligibility have obstructed speed and accessibility of administration,” he said.

One issue has been the reluctance of healthcare workers to be immunized, which has created a bottleneck as some states tried to finish vaccination of this group before moving forward. There are reports of vaccine reluctance and refusal in the Los Angeles area, with reports of from 20% to 40% of frontline nurses and doctors declining an initial offer of vaccine in L.A. County.1

Vanderbilt University realized it had a problem when it did a survey of healthcare workers in anticipation of receiving the vaccine, finding a surprising level of reluctance and hesitancy, says William Schaffner, MD, professor of health policy.

“One of the reasons these [public health] jurisdictions are now opening up is that people in 1a are not completely accepting the vaccine,” he says. “There is a fair amount of skepticism among healthcare providers.”

Finding this in their own staff, Vanderbilt ramped up educational activities and question-and-answer sessions to assure healthcare workers that the two available vaccines are safe and effective.

“It has helped move the needle,” Schaffner says. “More and more of our colleagues, employees, and staff are receiving the vaccine. We are not exactly where we want to be yet, but we keep working on that and going back to groups that are lagging. We’re making progress, but the lesson there is if it took that much work for healthcare workers, we have a have a lot of persuasion to do [in the community].”

Wide Variations in Practice

There has been much confusion and chaos about prioritizing the groups, with some states and localities ignoring Centers for Disease Control and Prevention (CDC) guidelines and vaccinating those perceived at highest risk in their area.

“As I talk to colleagues around the country and my state health department, they all say the same thing — there is extraordinary heterogeneity out there,” Schaffner says, adding that there are different policies within states, sometimes from institution to institution within the same county, between counties, and between states.

In that same vein, as this issue went to press, there were concerns and questions about whether the HHS has sufficient vaccine supplies to fulfill the deliveries described by Azar. If not, the critical question of whether there is a clear national distribution plan will again come to the fore.

Another point of contention is what happens to the carefully deliberated plans of the CDC Advisory Committee on Immunization Practices (ACIP). At a Dec. 20, 2020, meeting, ACIP voted to continue the rationing process while vaccine stocks are insufficient. ACIP designated the next priority groups for immunization while vaccine supplies are limited as follows; the estimated total population in each group is listed in parentheses.

1b: Persons age 75 years and older (21 million) and frontline essential workers (30 million). The latter group includes, for example, first responders, firefighters, police, teachers, food and agriculture workers, manufacturing workers, corrections workers, postal workers, public transit workers, and grocery store workers.

1c: Persons age 65 to 74 years (32 million); persons age 16 to 64 years with high-risk medical conditions, such as heart disease and diabetes (110 million); and other essential workers (37 million). The latter group includes, for example, workers in the transportation, food service, construction, finance, communications, energy, media, legal, public safety engineering, and water and wastewater industries.

With many critics saying the 65 to 74 age group should be prioritized over younger frontline essential workers, several states shifted the vaccination groups to do just that after the ACIP guidelines were released. Now, the HHS has broadened that move to include all those with high-risk medical conditions. Part of this change hinged on securing an ongoing vaccine supply, but the result appears to drop frontline essential workers down the priority list for the time being.

About 38 million total doses of vaccine — including 25 million first doses — have been made available for states, and more are on the way, Azar said.

“The doses allocated exceeds the priority populations in group 1a — including frontline health workers and seniors living in long-term care facilities — which means supply exceeds demand from those groups,” Azar said. “Over the last several days, we have averaged around 700,000 reported vaccinations each day and we are on track to hit 1 million per day in a week to 10 days’ time.”

Approximately 95% of long-term care facilities have had their first vaccination visit, he said.

“We are telling states they should open vaccinations to all people 65 and older and all people under age 65 with a comorbidity with some form of medical documentation as defined by governors,” Azar said. “This is the fastest way to protect the vulnerable and it is easier to allocate vaccines to people 65 and older and has enabled states to use much more diverse administration channels.”

With healthcare worker vaccine hesitancy and logistics an issue, some states have been holding back doses to complete the 1a group before proceeding.

“There was never a reason that states needed to vaccinate all healthcare providers before opening it up to older populations,” he said. “States should not be waiting to complete 1a priorities before proceeding to broader categories of eligibility. Think of it like boarding an airplane. You might have an order to board people, but you don't wait [until] everyone from a group is boarded. You have to keep the process moving.”

Shift to Community Settings

Hospitals have been the primary early vaccination sites, but outreach to broader populations means there will be more pharmacy involvement.

In addition, community health centers have more than 13,000 delivery sites across America, and they have convenient locations and strong connections in low-income and minority communities.

“We are making the full reserve of doses available” Azar said. “We are 100% committed to ensuring a second dose is available for every American who receives a first dose. Because we now have a consistent pace of production, we can now ship all of the doses that have been held in physical reserve, with second doses being supplied by doses coming off of manufacturing lines with quality control. Going forward, each week, doses available will be released to first cover the needed second doses and then cover additional first vaccinations.”

Effective Jan. 26, 2020, federal allocation to states will be based on their success in getting the vaccine to the most vulnerable, he said.

“We will be allocating based on the pace of administration as reported by states and by the size of the 65 and over population in each state,” Azar said. “We are giving states two weeks' notice of this shift to give them the time necessary to plan and improve their reporting if they think their data is faulty. This new system gives states the incentive to ensure that vaccinations are being reported and ensure that doses are going to work to protect people rather than sitting on shelves or freezers.”

Robert Redfield, MD, director of the CDC, said the agency is asking governors to “recommend the vaccination now be expanded to those individuals 65 and over and those individuals between 16-18 — depending on the vaccine — to 64 with a comorbidity with documentation. We clearly have enough vaccine to expand and get more and more of the vulnerable individuals vaccinated.”

This is particularly important right now, since we are seeing the post-holiday surge and there is the possibility of pushing hospital capacity to the breaking point, he noted.

“It is critically important to get those most vulnerable people, as quickly as we can, into vaccination programs as a key strategy to maintain hospital resilience," he said. “Using the approved antibodies for those that develop symptoms prior to hospitalization is a second important intervention to maintain hospital resilience.”

As the pandemic surges and frequently sets daily records for cases and deaths, masking and other mitigation strategies remain critical.

“Most of the transmission that is occurring in our nation is not occurring in the public square, but one household to one household to one household,” Redfield said. “Wear a mask. They work. Social distance, it works. Staying away and being smart about crowds, washing your hands, they work. We need to work all together now. Its going to be a difficult January and probably February, but with the vaccine and the new therapeutics we have, there is a strong light [at the end of the tunnel].

FDA Discourages Novel Vaccination Strategies

In a related development, the Food and Drug Administration (FDA) recently emphasized the importance of using the vaccines in a manner consistent with their clinical trials.

“We have been following the discussions and news reports about reducing the number of doses, extending the length of time between doses, changing the dose (half-dose), or mixing and matching vaccines in order to immunize more people against COVID-19,” the FDA stated in a letter.2

Although these are reasonable questions to consider and evaluate in clinical trials, “at this time, suggesting changes to the FDA-authorized dosing or schedules of these vaccines is premature and not rooted solidly in the available evidence,” the agency stated. “Without appropriate data supporting such changes in vaccine administration, we run a significant risk of placing public health at risk, undermining the historic vaccination efforts to protect the population from COVID-19.”

The available data continue to support the use of two specified doses of each authorized vaccine at specified intervals. For the Pfizer-BioNTech COVID-19 vaccine, the interval is 21 days between the first and second dose. For the Moderna COVID-19 vaccine, the interval is 28 days between the first and second dose.

“Using a single dose regimen and/or administering less than the dose studied in the clinical trials without understanding the nature of the depth and duration of protection that it provides is concerning, as there is some indication that the depth of the immune response is associated with the duration of protection provided,” the FDA states. “If people do not truly know how protective a vaccine is, there is the potential for harm because they may assume that they are fully protected when they are not, and accordingly, alter their behavior to take unnecessary risks.”


  1. Shalby C, Baumgaertner E, Branson-Potts H, et al. Some healthcare workers refuse to take COVID-19 vaccine, even with priority access. Los Angeles Times. Dec. 31, 2020.
  2. Food and Drug Administration. FDA statement on following authorized dosing schedules for COVID-19 vaccines. Jan. 4, 2021.