shot, the need for direct and clear guidance from the white house couldn't be more urgent. >> reporter: confusion and possible scaling back of the white house's covid-19 booster plan for september. less than a day after dr. anthony fauci said -- >> i would not at all be surprised that the adequate, full regimen for vaccination will likely be three doses. >> reporter: as the delta variant drives new covid cases in the united states to nearly 170,000 a day on average, new data shows a third so-called booster dose of the covid mrna vaccine provides more protection against the virus. >> there's no doubt from the dramatic data from the israeli study that the boosts that are being now done there and contemplated here support very strongly the rationale for such an approach. >> reporter: and making the case for boosters, fauci explaining israeli data shows they reduce