Even without complications, the flu can make you miserable and mean many days away from work or other responsibilities. You cannot get influenza from the vaccine. The flu shot is very safe and generally has few side effects. There may be some soreness, redness or swelling where the shot is given. Other possible mild side effects include a headache and low-grade fever for a day after you receive the shot.
Pneumonia is an infection in the lungs.
Pneumonia can be viral or bacterial. Pneumonia is transmitted in the air by coughing, sneezing or talking. Abrupt onset of fever, shaking chills, productive cough, pleuritic chest pain, shortness of breath and rapid heart rate. It is the fifth leading cause of death in adults each year. There are 500,000 cases of pneumonia each year.