Global coronavirus infections passed 65 million on Friday and countries doubled down on restrictions, even as plans to roll out vaccines gathered pace.
The US is among the countries posting all-time highs in daily deaths this week along with Italy, which is undergoing a dramatic resurgence after it largely tamped down its earlier outbreak by enforcing a strict lockdown in the spring.
The alarming spikes come after more positive news on vaccine development, with US-based Moderna announcing its candidate drug confers immunity for at least three months.
The pandemic is showing little sign of slowing, with the daily global death toll in recent weeks reaching its highest rate since the virus emerged in China late last year.
However, the rapid development of several vaccines has provided respite from the dismal cycle of lockdowns and surging cases.
Britain on Wednesday became the first Western country to approve a vaccine for general use, piling pressure on other countries to swiftly follow suit.
But Fauci said Britain had rushed its approval process.