Covid omicron booster shots should better protect against infection, serious illness

U.S. health officials expect new omicron boosters will provide better protection against infection and serious illness this fall because the new shots now match the dominant coronavirus variant.

The new omicron shots mark a milestone in the pandemic that will help the U.S. more effectively fight the virus, White House Covid response coordinator Dr. Ashish Jha said.

“For the first time since December of 2020, our vaccines have caught up with the virus,” Jha told reporters during a news conference on Tuesday.

Jha said the U.S. is moving to a point where most Americans will receive a single Covid shot every year that will provide a high degree of protection against the virus. People with serious medical conditions or weak immune systems might need additional shots.

The Food and Drug Administration and the Centers for Disease Control and Prevention last week cleared new booster shots for people ages 12 and older that target the dominant omicron BA.5 subvariant, as well as the original strain of Covid that first emerged in Wuhan, China, in 2019.

Jha said the FDA is working to make the new boosters available to children under 12 and switch the primary two-dose vaccine series to also target omicron.

Pfizer’s new booster is available for people ages 12 and up, while adults ages 18 and older can get Moderna’s shot. People can receive the new vaccine at least two months after their primary vaccination series or their most recent booster with the older shots.

Dr. Anthony Fauci, White House chief medical advisor, said the new boosters should provide better protection against omicron than the original vaccines. He added that it’s difficult to predict how much better they will perform.

Fauci said clinical data from Pfizer and Moderna on shots that targeted the original version of omicron, BA.1, triggered a stronger immune response against omicron and other Covid variants compared to the original vaccines. BA.1 is the variant the caused last winter’s massive surge.

Pfizer and Moderna were originally developing the omicron boosters to target BA.1, but the FDA asked the companies to switch gears in June and produce shots that targeted BA.5 as the subvariant rose to dominance.

As a consequence, they did not collect human data specifically on the BA.5 boosters. But FDA officials have said data from the BA.1 shots should give a good indication of how the BA.5 vaccines will perform because they are very similar.

“It is reasonable to expect based on what we know about immunology and the science of this virus that these new vaccines will provide better protection against infection, better protection against transmission and ongoing and better protection against serious illness,” Jha said.

Fauci said the clinical trials on the BA.1 shots, which were administered to more than 1,700 people, did not present any new safety concerns.

A new Covid variant could always emerge, but U.S. health officials will meet on annual basis to review whether the vaccines need a tweak to keep up with virus, Fauci said. He added that the new boosters should provide substantial protection even if BA.5 mutates slightly into a new subvariant.

The first generation Covid vaccines were more than 90% effective at preventing disease from Covid when they were first authorized in December 2020. But the protection provided by the old vaccines, which target the original Covid strain, has declined because the virus has evolved dramatically over the past two years into the highly immune evasive omicron variant.

Members of the CDC’s independent advisory committee last week expressed some concern about the lack of human data on the BA.5 shots. They still recommended the new boosters in an overwhelming 13 to 1 vote, reasoning that the potential benefits of the vaccines outweigh any risks.

CDC Director Dr. Rochelle Walensky said the new boosters could prevent as many as 100,000 hospitalizations and 9,000 deaths. She added that the shots could save billions in medical costs if people receive them at the same level as annual flu vaccine coverage.

Those figures are based on a forecast from a consortium of scientists called the Covid-19 Scenario Modeling Hub. The model assumes the new boosters will provide 80% protection against disease.

Health and Human Services Secretary Xavier Becerra said health officials will focus on making sure people who face higher risk from Covid, particularly people ages 50 and up, get boosted with the new shots this month.

CVS and Walgreens began offering appointments for the new shots over the weekend. By the end of this week, 90% of Americans will live within 5 miles of a location where they can receive the new boosters, Becerra said.

You can visit vaccines.gov to find a location offering the shots.

Jha said the Biden administration has asked for additional funding from Congress to develop next generation vaccines that can keep up with the virus over the long term.