41°F
weather icon Clear

Pfizer says COVID booster adds protection against omicron

Pfizer said Wednesday that a booster dose of its COVID-19 vaccine may offer important protection against the new omicron variant even though the initial two doses appear significantly less effective.

Pfizer and its partner BioNTech said that while two doses may not be protective enough to prevent infection, lab tests showed a booster increased by 25-fold people’s levels of virus-fighting antibodies against the omicron variant.

Blood samples taken a month after a booster showed people harbored levels of omicron-neutralizing antibodies that were similar to amounts proven protective against earlier variants after two doses.

Scientists don’t yet know how big a threat the omicron variant really is. Currently the extra-contagious delta variant is responsible for most of the COVID-19 cases in the U.S. and other countries.

But the omicron variant, discovered late last month, carries an unusually large number of mutations and scientists are racing to learn how easily it spreads, whether it causes illness that is more serious or milder than other coronavirus types — and how much it might evade the protection of prior vaccinations.

Pfizer’s findings, announced in a press release, are preliminary and haven’t yet undergone scientific review. But they’re the first from a vaccine maker examining whether the booster doses that health authorities are urging people to get may indeed make an important difference.

Scientists have speculated that the high jump in antibodies that comes with a third dose of COVID-19 vaccines might be enough to counter any decrease in effectiveness.

Pfizer and BioNTech already are working to create an omicron-specific vaccine in case it’s needed.

Antibody levels predict how well a vaccine may prevent infection with the coronavirus but they are just one layer of the immune system’s defenses. Pfizer said two doses of the vaccine should still protect against severe disease, because the mutations in omicron don’t appear to hamper one of those other defenses, T cells that fight the virus after infection sets in.

“Although two doses of the vaccine may still offer protection against severe disease caused by the Omicron strain, it’s clear from these preliminary data that protection is maximized with a third dose of our vaccine,” Pfizer CEO Albert Bourla said in a statement.

Pfizer’s announcement had an immediate impact on U.S. markets. Futures that had pointed to a lower open reversed course in seconds and swung solidly to the positive with the Dow jumping almost 200 points.

Don't miss the big stories. Like us on Facebook.
THE LATEST
Biden to highlight progress, ask for patience during news conference

The East Room event will offer Biden an opportunity to spotlight his accomplishments before a national audience, and he was sure to highlight the bipartisan infrastructure law enacted on his watch.

Airlines cancel, change flights to US over 5G dispute

It wasn’t immediately clear whether airlines took into account that mobile carriers AT&T and Verizon agreed this week to pause the rollout of the new high-speed wireless service near key airports.

Website launches for ordering free COVID-19 home tests

The Biden administration on Tuesday quietly launched its website for Americans to request free at-home COVID-19 tests, a day before the site was scheduled to officially go online.

Storm Izzy pummels third of country, heads up East Coast

Tens of thousands of customers were without power in Georgia, North Carolina, South Carolina and Florida. Highway patrols reported hundreds of vehicle accidents, and a tornado ripped through a trailer park in Florida.

 
More worrisome variants expected after omicron, scientists say

“The faster omicron spreads, the more opportunities there are for mutation, potentially leading to more variants,” Leonardo Martinez, an infectious disease epidemiologist at Boston University, said.

‘Prayers answered’: All Texas synagogue hostages safe, captor killed

Authorities said a man took hostages Saturday during services at a Texas synagogue where the suspect could be heard ranting in a livestream and demanding the release of a Pakistani neuroscientist who was convicted of trying to kill U.S. Army officers in Afghanistan.

Your missing package may have been stolen from LA train

Thieves have been raiding cargo containers aboard trains nearing downtown Los Angeles for months, taking packages belonging to people across the U.S. and leaving the tracks blanketed with discarded boxes.

 
How to request a free COVID test kit

A new federal website to request free test kits launches Wednesday, with the first shipments going out to Americans by the end of the month.

Supreme Court stops vaccine mandate for US businesses

The Supreme Court has stopped the Biden administration from enforcing a requirement that employees at large businesses be vaccinated against COVID-19 or undergo weekly testing and wear a mask on the job.