Flu vs. Pneumonia — What's the Difference?

Influenza

Pneumonia is an inflammatory condition of the lung primarily affecting the small air sacs known as alveoli. Symptoms typically include some combination of productive or dry cough, chest pain, fever and difficulty breathing.

Influenza.

Lung inflammation caused by bacterial or viral infection, in which the air sacs fill with pus and may become solid. Inflammation may affect both lungs (double pneumonia) or only one (single pneumonia).

Any of several infections that affect the respiratory or gastrointestinal tract and are caused by viruses other than the influenza virus.

An acute or chronic disease marked by inflammation of the lungs, usually caused by a bacterium, virus, or other infectious agent.

Influenza.

An acute or chronic inflammation of the lungs caused by viruses, bacteria or other microorganisms, or sometimes by physical or chemical irritants.

(informal) Stomach flu.

Inflammation of the lungs.

An acute febrile highly contagious viral disease

Respiratory disease characterized by inflammation of the lung parenchyma (excluding the bronchi) with congestion caused by viruses or bacteria or irritants