The director of the C.D.C. said U.S. health officials “should be treating every case as if it’s a variant.”
Reports of new coronavirus cases have dropped by more than a third in recent weeks, reaching their lowest levels since November. Forty-eight states are reporting sustained declines in new infections.
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A new vaccine
Johnson & Johnson, the only major drugmaker developing a single-dose Covid vaccine, announced on Friday that its shot had provided strong protection in clinical trials.
If the Food and Drug Administration grants the company an emergency authorization, it would expand the vaccine supply in the United States as the Biden administration seeks to immunize many more Americans.
The results came with a significant cautionary note: In the U.S., the vaccine had an efficacy rate of 72 percent in clinical trials. But in South Africa, a country gripped by a new and more contagious variant, the efficacy rate dropped to just 57 percent.
The variant, which has spread to at least 31 countries, including the United States, may also blunt the effectiveness of Covid vaccines made by Pfizer-BioNTech, Moderna and Novavax.
Dr. Anthony Fauci, the top U.S. infectious disease expert, warned that Johnson & Johnson’s trial results were a “wake up call” and warned manufacturers to be ready to reformulate the vaccines if needed.
“If ever there was reason to vaccinate as many people as expeditiously as we possibly can with the vaccine that we have right now, now is the time,” Dr. Fauci said in an interview.
Scientists still consider the Johnson & Johnson vaccine to be a success: It was 85 percent effective in preventing severe disease. In all three regions where the trial was run — the United States, Latin America and South Africa — after 28 days, none of the vaccinated participants who developed Covid-19 had to be hospitalized. It is also easier to transport and administer than its rivals.
The Moderna and Pfizer vaccines need to be stored at extremely low temperatures, and they spoil quickly once thawed. That could make Johnson & Johnson’s vaccine easier to distribute in poorer parts of the world, where more aggressive mutants could otherwise be seeded.
Meanwhile in Europe: The E.U. approved AstraZeneca’s coronavirus vaccine but moved to temporarily restrict doses made in the bloc from being shipped abroad. Britain, a former bloc member, had been receiving a steady flow of vaccine doses from AstraZeneca since approving it well ahead of the E.U. in early December.
The New York Times