But Hamilton woke up Monday morning with mild symptoms and was then informed that a contact prior to arrival in Bahrain had subsequently tested positive, his Mercedes team said Tuesday.
In order to compete for Mercedes, Russell had to be released by Williams temporarily.
LEWIS HAMILTON has been left "devastated" after being ruled out of this weekend's Sakhir Grand Prix by coronavirus on the same day he was confirmed as favourite to be named BBC Sports Personality of the Year.
Mercedes boss Toto Wolff said that his thoughts were with Hamilton while pointing out that the team still had a job to do this weekend.
The starting grid will be without its biggest name under the floodlights, with only Alfa Romeo's Kimi Raikkonen having raced in the pre-Hamilton era, but that opens up opportunities for others.
The news that Hamilton would miss the next race came as it was announced he would once again be a contender for the prestigious BBC Sports Personality of the Year award. "It's very optimistic but I know he's very good. If I get the opportunity next week in Abu Dhabi, who knows, that will be easier". The team has two reserve drivers, Belgian Stoffel Vandoorne and Esteban Gutierrez of Mexico.
"I'm absolutely over the moon to have the opportunity to make my debut with Williams this coming weekend and I am extremely happy for George to have his chance too", Aitken said.
Pfizer's first coronavirus vaccine doses to arrive in United Kingdom in 'coming days'
The 975 doses they contain would be too many for individual care homes, meaning the vaccine would be wasted, he explained. It's expected to be given to healthcare workers first, followed by residents of care home.
"Obviously, I will try to avoid that".
In terms of the track, it's not the first time this year that we're staying at the same facility for two weeks running, but I like that they've changed this one up a bit with the shorter "outer" layout.
"There's no targets and no expectations because you can't judge somebody off the back of one race. The future will be judged over the course of a season, and what's happened in the past, not just one or maybe two races".
He was Mercedes reserve driver in 2017 and 2018 and has done just over 6,500km of testing for the team but has not even driven the 2020 vehicle in the team's simulator.
"I was actually in the bathroom, which was slightly awkward".
"Our long-term partnership and George's affiliation with Mercedes is no secret, and so I'm delighted George has this unique opportunity to join Mercedes, the current Constructors' Champions", Williams' Acting Team Principal, Simon Roberts said in a statement.
With Mercedes development driver Russell vacating his seat with Williams for the second race in Bahrain, Jack Aitken will make his Formula One race debut with the British team.