Patricia was called at work by a woman at the local daycare center. She told Patricia to come and ...

Influenza is characterized by a rapid onset of symptoms, particularly malaise. The common cold has a less aggressive onset with the initial appearance of nasal sinus irritation and excessive nasal secretions.
A proper investigation prevents the unwarranted use of antibiotics in a symptomatic patient. The reporting of influenza to public health authorities also contributes to the accurate monitoring of contagious illness within a population.

The influenza A virus damages the epithelial cells of the respiratory tract. They undergo necrosis and shed away to leave gaps between underlying basal cells. Extracellular fluid escapes through the basal membrane and contributes to fluid accumulation in the respiratory passages. Damaged ciliated cells are unable to move mucous within the airways, so mucous accumulation and congestion become an additional component to the infection.
Surface antigen HA facilitates the movement of the influenza A virus into the epithelial cells of the respiratory tract. The NA glycoprotein promotes viral replication and release from the host cell.

Viruses damage the protective mucous membranes in the nasopharynx. Because they also encourage mucous secretions, macrophage activity on pneumococci is inhibited while bacterial adhesion to the epithelium is enhanced. Pneumonia is a condition that causes inflammation of the alveoli. Cyanosis occurs as a result of the decrease in gas exchange through the inflamed alveolar membrane and subsequent decline in hemoglobin saturation.