The player sustained an injury to his left thigh during the second day of the first Test match in Chattogram, and the coaches closely monitored him. Shakib experienced discomfort in his left hand while trying to stop a ball off his own bowling.
He was neither able to bat nor bowl during the second innings of the game against West Indies in Chittagong.
After assessing Shakib's current condition, the coaches have concluded that he's not entirely fit and is yet to recover from the strain.
''Shakib will leave the team bio-security bubble this week and for the time being will be under the surveillance and treatment of the BCB medical in Dhaka as he continues to recover and consolidate his physical robustness,'' said BCB in a statement.
The 33-year-old player had previously suffered a groin niggle during their third ODI match on January 25 against the Carribean side. The Bangladesh Cricket Board monitored him closely and advised him to rest for a few days before joining the senior team for the test series.
Selectors haven't announced a replacement for Shakib Al Hassan and are most likely to continue without any new players in the squad.
BAN v WI 2021: Second Test to begin on February 11
The second Test between Bangladesh and West Indies will take place between 11th and 15th February at the Sher-e-Bangla National Cricket Stadium in Dhaka.
West Indies lead the series 1-0 and will look to win the final Test and take home the trophy, while Bangladesh will look to bounce back from the loss and level the series.