Rendering of a coronavirus molecule suspended with others on a blue and purple background

The Pfizer-BioNTech vaccine is less effective against omicron, but cases caused by this mutation of the SARS-CoV-2 virus are milder, according to a real-world study released Tuesday.

The news comes alongside warnings that omicron is spreading more quickly than previous variants. Currently it accounts for only about 3% of U.S. COVID-19 cases, according to the Centers for Disease Control and Prevention. But the number of omicron-related cases have jumped sevenfold in a single week, federal health officials have announced.

A large wave of omicron-related infections is expected to peak in January, they said during a Tuesday press briefing.

The new vaccine efficacy study — yet to be peer-reviewed — was conducted in South Africa, where the variant was first detected and is now dominant. It revealed that having two doses of the shot lowered the odds of contracting COVID-19 by 30%, versus the 80% protection it has been shown to deliver against the delta variant. The vaccine also cuts hospitalization with the disease by 70%, compared with 93% during the delta wave, Reuters reported

But some experts continue to take a wait-and-see approach to the new findings. Hospitalization increases may occur weeks after an infections surge, they told the Associated Press.

U.S. health officials expressed measured confidence that a full course of vaccinations plus a booster should protect against illness and death from all circulating variants — including omicron, according to the Washington Post. But more booster coverage is needed, they said.

In the United States, more than 54 million people have received an additional shot. That’s out of 200 million who are fully vaccinated with the initial course of shots, the news outlet reported.

Long-term care facilities, meanwhile, continue to manage the fallout from the delta surge, and some U.S. hospitals are again inundated by an influx of patients due to that variant, various news sources have reported. The National Guard has been called in to provide support to LTC facilities in Maine and healthcare systems in that state, Indiana and New Hampshire, according to the New York Times.

Pfizer’s experimental COVID-19 pill proves 89% effective in latest analysis

In related news, Pfizer’s experimental COVID-19 pill has been confirmed as highly effective against COVID-19.

In a clinical trial involving more than 2,000 high-risk patients, the drug Paxlovid (nirmatrelvir) was 88% effective at preventing hospitalization and death within five days of symptom onset, the drugmaker reported Tuesday.

Paxlovid is in line for emergency use authorization from the Food and Drug Administration. Study subjects had mild to moderate COVID-19 and at least one condition putting them at high risk of severe outcomes, the drugmaker reported. They received the drug or a placebo orally every 12 hours for five days.

The trial outcomes are especially encouraging when compared to the performance of another highly anticipated COVID-19 oral medication. The drug molnupiravir, developed by Ridgeback Biotherapeutics and Merck, has been shown to reduce the odds of serious illness and hospitalization by 30% in patients with COVID-19. That’s compared to the 50% reduction trial data had suggested previously. 

Molnupiravir was recommended for emergency use authorization by FDA advisers in early December, but the agency has not yet given it the green light. 

The authorization of an orally delivered COVID-19 medication is expected to be a pandemic game-changer, potentially allowing certain high-risk patients to be more easily treated at home.