WATERTOWN, N.Y. (WWTI) — There is ongoing confusion regarding the difference between the now approved COVID-19 booster shot and a third dose of a COVID-19 vaccination.

Generally, these shots have different eligibility requirements. Starting with the third dose, Jefferson County Public Health Service’s Faith Lustik, who is the county’s health planner, shared that the third dose is specifically for immunocompromised individuals who have received an mRNA COVID-19 vaccine.

“So the third dose is for people who are immune-compromised, who got their second shot, but it didn’t give them enough immune response,” Lustik shared. “So it didn’t stimulate their immune system to have the full protection.”

A third dose of the coronavirus vaccine can be administered at least 28 days after receiving the second dose of either vaccination to specific individuals.

This includes those in active treatment for solid tumor and hematologic malignancies, organ transplant and stem-cell transplant patients, those with moderate or several primary immunodeficiencies, advanced or untreated HIV infection and those undergoing treatment with high-dose corticosteroids.

Regarding the COVID-19 booster shot, this vaccination essentially, “boosts” an individual’s immune system as it wanes over time.

“We know that over time, your immunity is waning. That’s true for all immunity, it wanes over time,” Lustik added. “So we know that now people need a third dose, that we call a booster dose and that’s because it’s boosting your immune system back up to where it was to begin with.”

Health experts stated that those 65 years and older and residents in long-term care settings should receive a COVID-19 booster shot, as well as those 50 to 64 years old with underlying medical conditions.

Additionally, individuals who are aged 18 to 49 years old with underlying medical conditions, or who are at increased risk for COVID-19 exposure and transmission because of an occupational or institutional setting are eligible for a booster shot.

Booster shots were approved in New York State on September 24. Currently, the only booster shot authorized for administration is the Pfizer-BioNTech mRNA vaccine/ Those who received the Moderna or Johnson & Johnson COVID-19 vaccine are not eligible for booster shots.

Both the third dose of the COVID-19 vaccine and booster shots are available at local and state-run vaccination sites, pharmacies and some medical providers offices in New York State.