(CNN) Advisers to the US Food and Drug Administration are scheduled to meet Wednesday to get a clearer picture of what the future of Covid-19 booster shots might look like.
Just last week, the FDA expanded the emergency use authorization of the Pfizer/BioNTech and Moderna vaccines to allow adults 50 and older to get a second booster shot as early as four months after their first booster dose of any Covid-19 vaccine.
But there has been some debate around whether additional doses of Covid-19 vaccine will be needed for the general public -- and, if so -- when and how often.
The FDA's Vaccines and Related Biological Products Advisory Committee will discuss the possible need for Covid-19 vaccine booster shots in the future, including the process for selecting variant-specific boosters and whether the Covid-19 vaccine could become an annual shot.
Americans might need to be ready for booster shots to become an annual occurrence, similar to how flu shots are recommended each year, Dr. Anthony Fauci, chief medical adviser to President Joe Biden, said Friday.
"We don't know this as a fact, but it could be that we may need an intermittent boost on a yearly basis until we get this level so low down," Fauci, who is also the director of the National Institute of Allergy and Infectious Diseases, told CNN's Chief Medical Correspondent Dr. Sanjay Gupta on "Interview Club" on CNN+.
The goal is to get the circulating coronavirus to such low levels that it does not affect society, Fauci said.
"We want to get it to such a low level that it does not interfere at all with us, and if that does require a yearly vaccine that might be adjusted to a new variant, just the same way we adjust the influenza vaccines, we'll just have to wait and see," Fauci said. "We need to be prepared for that."
The FDA vaccine advisory meeting is intended to help develop a "general framework" that will inform when Covid-19 booster doses might be needed and what might warrant updating the formulation of vaccines to target specific coronavirus variants, the FDA noted last month.
"As we prepare for future needs to address COVID-19, prevention in the form of vaccines remains our best defense against the disease and any potentially severe consequences," Dr. Peter Marks, director of the FDA's Center for Biologics Evaluation and Research, said in a statement.
"Now is the time to discuss the need for future boosters as we aim to move forward safely, with COVID-19 becoming a virus like others such as influenza that we prepare for, protect against, and treat," Marks said. "Bringing together our panel of expert scientific external advisors in an open, transparent discussion about booster vaccination is an important step to gain insight, input and expert advice as we begin to formulate the best regulatory strategy to address COVID-19 and virus variants going forward."
The agenda for Wednesday's meeting includes an update from experts on the coronavirus variants that have been identified during the pandemic, as well as presentations on predicting variants, the effectiveness of vaccines on children and adults, and what Israeli data shows about the use of fourth doses in older adults.
FDA advisers are scheduled to hear from Israeli Director of Public Health Services Dr. Sharon Alroy-Preis. Representatives from the US Centers for Disease Control and Prevention and the National Institutes of Health are also scheduled to participate.
The FDA's vaccine advisers will hear from experts at the University of Washington's Institute for Health Metrics and Evaluation in Seattle on modeling future Covid-19 outbreaks.
Experts from the World Health Organization and the US Biomedical Advanced Research and Development Authority are scheduled to speak on variants and developing future vaccines.
The final presentation on the agenda is from the FDA's Office of Vaccines Research and Review on a proposed framework for addressing future Covid-19 outbreaks. That will be followed by a lunch break, then an open public hearing and finally a committee discussion.
No official vote is planned at the meeting, and there will be no discussion of any specific products applying for authorization or approval.
To keep the coronavirus under control in the future, "we likely will need some form of periodic vaccination. Now, whether that's annual or every two years or every five years, we don't really know that yet. I think that that will emerge as we gather more data," Dr. Archana Chatterjee, dean of the Chicago Medical School at Rosalind Franklin University and a member of the vaccine advisory committee, told CNN in March.
"But I do anticipate that this will be required on a periodic basis to keep it under control," said Chatterjee, who added that her comments do not reflect the opinions of the committee or the FDA.
For now, "there are two issues that are going on" when it comes to the future of Covid-19 booster shots, Fauci said Friday.
There is the immediate issue around what the future might look like for adults 50 and older, who are now eligible to receive fourth doses -- or a second booster shot -- of Covid-19 vaccine.
"Will my getting a vaccine now somehow interfere with the effectiveness if I need a boost in the fall?" Fauci speculated. "It could possibly be that if the protection starts to wane, those of us in a certain category age-wise or underlying condition might actually require that additional boost, and getting it now for the elderly individual should not impede at all the feasibility of your getting it as we enter into the fall."
The second issue, Fauci said, is more long-term and involves establishing what exactly the future might look like for the general public regarding how often booster shots could be needed, if at all.
Because, according to Fauci, the hopeful question around levels of circulating virus remains: "Will it ultimately get to such a low level that we might not even need a boost every year?"