Definition of Upper Respiratory Infection
An upper respiratory infection (URI) is an acute infection of the nose, sinuses, pharynx, and larynx that is typically viral in origin, characterized by symptoms such as nasal congestion, rhinorrhea, sore throat, and cough, where sinus, pharyngeal, and lower airway symptoms may be present but are not prominent. 1
Clinical Characteristics
URIs are predominantly viral infections that affect the upper respiratory tract structures including the mouth, nose, throat, larynx (voice box), and trachea (windpipe). 1, 2
Key Diagnostic Features
- Viral etiology is the norm: The vast majority of URIs are caused by viral pathogens, not bacteria 1
- Self-limited course: Most uncomplicated URIs resolve spontaneously within 1-2 weeks, with most patients improving within the first week 1
- Common symptoms include: sneezing, rhinorrhea, nasal congestion, postnasal drip, sore throat, cough, ear fullness/pressure, low-grade fever, headache, malaise, and hyposmia/anosmia 1
Critical Distinction from Bacterial Infections
Purulent nasal discharge and sputum do NOT predict bacterial infection and should not be used as justification for antibiotic therapy. 1 This is a common pitfall—the color or character of nasal discharge is not a specific sign of bacterial superinfection. 1
Conditions Included Under URI
The term "nonspecific URI" encompasses several clinical presentations: 1, 2
- Common cold (viral rhinitis): The most common acute illness, presenting with mild upper respiratory symptoms 1
- Acute cough illness/acute bronchitis: Cough-predominant viral illness 1
- Nonspecific upper respiratory symptoms: When sinus, pharyngeal, and lower airway symptoms are present but not prominent enough to warrant specific diagnoses 1
What URI Does NOT Include
Important caveat: The diagnosis of nonspecific URI should be distinguished from specific bacterial infections that may require antibiotics: 1
- Acute bacterial rhinosinusitis (occurs in fewer than 2% of viral URIs) 1
- Group A streptococcal pharyngitis 1
- Acute otitis media 1
- Bacterial pneumonia 1
Clinical Implications
Antibiotics are NOT indicated for uncomplicated URIs because they do not enhance illness resolution, alter rates of complications, decrease symptom duration, or prevent lost work time. 1 The primary management strategy should focus on symptomatic relief with analgesics, antipyretics, and supportive care. 1
Bacterial complications are rare, occurring in less than 2% of viral URIs, and antibiotic therapy does not prevent these complications. 1