Description

• Inflammation of nasal passages resulting from infection with respiratory viruses
• Most cases are mild to moderate in severity, self-limited, and amenable to self-treat.
• System(s) affected: ENT; pulmonary

Epidemiology

• Each virus has different seasonal peaks (e.g., rhinovirus: late spring, fall); most infections occur during the winter months.
• Symptoms usually peak in 1 to 3 days, lasting up to 2 weeks.
• Transmission:
  • Contact with contaminated skin/surface followed by contact with mucous membranes (hand-to-face contact)
  • Aerosolized particles from sneezing and coughing
• Viruses may last up to 2 hours on skin and even longer on environmental surfaces.

Incidence

• Predominant age: children > adults
  • Preschool children: 5 to 7 URI per year
  • Kindergarten: 12 URI per year
  • Schoolchildren: 7 URI per year
  • Adolescents/adults: 2 to 3 URI per year
• Predominant sex: male = female

Etiology and Pathophysiology

Rhinoviruses infect the ciliated epithelial mucosa of the upper airway, resulting in edema, hyperemia, and mucous production.

• Histology: edema of subepithelial connective tissue and a scanty cellular infiltrate containing neutrophils, plasma cells, lymphocytes, and eosinophils with exudation of serous and mucinous fluid
• Rhinovirus causes a “nondestructive” inflammation of the mucous membranes.
• Influenza and parainfluenza viruses denude respiratory epithelium to the basement membrane.
• Several hundred viral strains from different families; spread within geographic region and groups with close contact
  • Rhinovirus (>100 serotypes): 30–50%; incubation period 1 to 5 days
  • Influenza virus types A, B, C: 10–15%; incubation period 1 to 4 days
  • Coronaviruses: 10–15%
  • Parainfluenza, respiratory syncytial virus (RSV): 5%; more common in children; incubation period 1 week
  • Enteroviruses, adenoviruses: <10%
• In many cases, no specific pathogen is identified.

Risk Factors

• Exposure to infected people
• Touching one’s face with contaminated fingers
• Allergic disorders
• Smoking
• Immunosuppression
• Stress

General Prevention

• Frequent hand washing, especially in children
• Limiting exposure to infected persons/children

Commonly Associated Conditions

• Pharyngitis
• Sinusitis
• Otitis media
• Bronchitis
• Bronchiolitis
• Pneumonia
• Croup
• Asthma