Hi, Welcome to Health care magic forum.
The weight gain after the recovery from the
typhoid fever is a rare thing.
The drugs or the fever it self might have an effect on the
kidney or
liver which might have a weight gain.
Or the convalescence would have an extra care,and extra diet.
I advise you to consult a physician for diagnosis whether there is any renal or liver effects.
Other wise Keep the weight under control by by cutting the calories, sweets, and fatty foods.
Practice morning walk,
yoga, exercises, and keep on working some thing, like doing any work in front.
Minimize the sleeping time, practice late to bed and and early to rise.
Wishing for a quick and complete recovery. Thank you