What Causes Losing Sense Of Taste And Smell Post Treatment For Pneumonia?

I lost my sense of taste & smell after a long bout (3 weeks) of pneumonia in December. Treatment included 2 rounds of antibiotics, an antibiotic injection, Prednisone for 7 days, nebulizer breathing treatments with a steroid and Albuterol for about a month. My doc said I should be back to normal in a couple of months, but there s no change yet. What do you think caused the problem and why hasn t it reversed itself? I have been treated with all of the meds in the past without any problem.