US has a "very serious" problem with Covid-19 vaccine uptake

The United States has a "very serious" problem with Covid-19 vaccination uptake, a top health official has warned.

Vaccines are by far the most powerful tool available against the coronavirus, protecting people from getting seriously ill, being hospitalized, and dying from the virus.

Unlike many less developed countries, the US has enough doses to vaccinate everyone as well as the necessary infrastructure to support the rollout.

The problem: not everyone wants the shot.

"We do have a problem with vaccine uptake that is very serious in the United States and anything we can do to get people more comfortable to be able to accept these potentially life-saving medical products is something that we feel we are compelled to do," said Dr. Peter Marks, director of the Center for Biologics Evaluation and Research.

According to the US Centers for Disease Control and Prevention, 48.7% of people over the age of 12 have been fully vaccinated and received at least one booster dose in the US.

That is a lower rate than in other countries with similar access to vaccines. For example, 69.6% of people over the age of 12 have been boosted in the United Kingdom and 55.5% in Canada. Across the 27 European Union countries, 62.6% of adults have been boosted.

Marks was speaking to the US Food and Drug Administration (FDA) Vaccines and Related Biological Products Advisory Committee, as it considered the approval of a new Covid-19 vaccine developed by the US biotechnology company Novavax on Tuesday.

The committee voted overwhelmingly in favor of approving the vaccine, saying its emergency authorization by the FDA would be beneficial, CNN's Jacqueline Howard writes.

Vaccine hesitancy was among the topics discussed in the meeting.

The Novavax Covid-19 vaccine uses different technology from the three vaccines currently in use in the US and so it might be an option for people allergic to an ingredient used in mRNA vaccines.

Asked why there is a need for another Covid-19 vaccine in the United States when three vaccines have already been authorized for use -- Pfizer/BioNTech, Moderna and Johnson & Johnson's Janssen, the latter a non-mRNA shot -- Marks responded: "The Janssen vaccine is currently not being used as a frontline vaccine, the same way as the mRNA vaccines, which leaves the issue of vaccines for those who might not want to take an mRNA vaccine because of concerns they might have with an mRNA vaccine."

The FDA in May limited the emergency use authorization of Johnson & Johnson's Janssen Covid-19 vaccine to adults who cannot or will not have another type of vaccine, because of the risk of a rare and dangerous clotting condition after receiving it.

Novavax's Covid-19 vaccine -- administered as two doses three weeks apart -- is made using small laboratory-built pieces of the coronavirus to stimulate immunity.

This protein-based approach is a more traditional method of vaccine development than the mRNA vaccines from Pfizer/BioNTech and Moderna.