The powerful protection offered by Moderna’s Covid vaccine does not wane in the first six months after the second dose, according to a statement released by the company on Thursday morning in advance of its earnings call.

But during the call, Moderna executives said they anticipated that boosters would be necessary this fall to contend with the Delta variant, which became common in the United States after the results were collected.

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A batch of early coronavirus data that went missing for a year has emerged from hiding.

In June, an American scientist discovered that more than 200 genetic sequences from Covid-19 patient samples isolated in China early in the pandemic had puzzlingly been removed from an online database. With some digital sleuthing, Jesse Bloom, a virologist at the Fred Hutchinson Cancer Center in Seattle, managed to track down 13 of the sequences on Google Cloud.

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Pfizer reported on Wednesday that the power of its two-dose Covid vaccine wanes slightly over time, but nonetheless offers lasting and robust protection against serious disease. The company suggested that a third shot could improve immunity, but whether boosters will be widely needed is far from settled, the subject of heated debate among scientists.

So far, federal health officials have said boosters for the general population are unnecessary. And experts questioned whether vaccinated people should get more doses when so many people have yet to be immunized at all.

Continue reading “Citing New Data, Pfizer Outlines Case for Booster Shots” →

As Israel struggles with a new surge of coronavirus cases, its health ministry reported on Thursday that although effectiveness of the Pfizer-BioNTech vaccine remains high against severe illness, its protection against infection by the coronavirus may have diminished significantly compared with this winter and early spring.

Analyzing the government’s national health statistics, researchers estimated that the Pfizer shot was just 39 percent effective against preventing infection in the country in late June and early July, compared with 95 percent from January to early April. In both time periods, however, the shot was more than 90 percent effective in preventing severe disease.

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