Upon returning to the UK for the fit, Bottas was required to self-isolate for a week which he described as "not too bad" and "better than expected".
Last year he finished second in the drivers' standings to team-mate Lewis Hamilton, finishing 124 points adrift of the seven-time champion after taking two race wins to the Briton's 11.
The Finn, Hamilton and Mercedes young driver George Russell, who will race at Williams for a third successive year, are all out of contract at the end of this year.
After Russell's strong showing against Bottas in the Sakhir Grand Prix, the 31-year-old knows how important it will be for him to perform at a consistently high level throughout the record-breaking 23-race season.
Unsurprisingly, Mercedes enter the year as favourites to take an eighth drivers' and constructors' championship double as it has yet to be beaten in the current V6 turbo-hybrid era.