Though the first COVID-19 bivalent booster was not well-received when it launched last year, U.S. public health officials have started discussing rolling out another round of bivalent booster doses.

A source familiar with the deliberations told CNN on condition of anonymity this week that health authorities have already started to weigh whether the country should offer people at high risk of severe Covid the chance to get another bivalent booster.

The bivalent booster was designed with two kinds of instructions. The first allowed the formula to recognize the ancestral strain of COVID-19. The second enabled it to identify and target the omicron variant and its newer descendants.

The U.S. government officially rolled out the bivalent booster last September. It has been six months since then, so experts have begun discussing the need for another dose to extend the immune protection against the novel coronavirus.

It is important to note that the first bivalent booster was not as well-received by the public as experts had hoped. Data from November to December 2022 showed that only 27.1% of adults and 18.5% of adolescents received a bivalent booster after completing their primary vaccine series, according to the Centers for Disease Control and Prevention (CDC).

Despite the poor reception, it’s still highly likely for the country to offer another dose since the bivalent booster provides the highest protection against the virus so far, even though it wanes over time.

Last week, the U.S Food and Drug Administration (FDA) was still undecided on the rollout of spring booster even though at-high-risk individuals had started to ask clinics and hospitals for another jab to stay protected.

“We continue to closely monitor the emerging data in the United States and globally, and we will base any decision on additional updated boosters upon those data. Importantly, individuals who have not yet received an updated (bivalent) booster are encouraged to speak with their health care provider and consider receiving one,” an FDA spokesperson told CNN via email.

Meanwhile, experts urged the FDA to phase out the monovalent COVID-19 vaccines since they only offered protection against the original strain of COVID-19 and not the newer variants and subvariants.