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Recovery time is individualized. In this patient, the patient's age and presence active infection are hinderance to recovery time.
Presuming this gentleman is otherwise normal and active and his infection is under control, the cause of weakness is attributed to mainly anemia
secondary to blood loss. This can be corrected with oral as well as injectable iron supplements
in 2-3 months. This patient should be able to become normal in this time frame.
It is important that the number of visitors be restricted till his infection is bought in control. It is equally important that he is on iron rich diet and physicial activity is slowly initiated.
Hope this helps.
I wish this gentleman a speedy recovery.