Upper Respiratory Infection


Upper Respiratory Infection, Infectious Rhinitis, Viral Rhinitis, Common Cold

  • Pathophysiology
  1. Infection of ciliated epithelial cells in nasal mucosa
  2. Nasal Discharge results from mild cell inflammation
    1. Increased local production of mucus, Immunoglobulin
    2. Shedding epithelial cells
  3. Bacterial adherence increases with Viral Infection
    1. Superinfection risk (higher in smoke exposure)
  4. Wet weather and chilling do NOT increase Infectivity
  • Epidemiology
  1. Peak months (related to congregation in confined space)
    1. Temperate climate: September to March
    2. Tropics: Rainy season
  2. Annual Incidence
    1. Children: 6-8 URIs per season (higher in daycare)
    2. Adults: 2-4 URIs per season
  3. Course
    1. Incubation: 48-72 hours (may be as long as 7 days)
    2. Viral Shedding
      1. Peaks with symptoms
      2. Persists as long as 2-3 weeks
    3. Symptoms peak by days 3-5
  4. Transmission
    1. Aerosol transmission predominates
    2. Hand to hand to nose (and eye) transmission is common
      1. Hands are virally contaminated 60% of time
      2. Hand Washing with virucidal agents is effective
    3. Fomite transmission (e.g. toys) is inconsistent
  • Etiologies
  1. Most Common cause: Rhinovirus (30-50%)
  2. No Etiology identified (35%)
  3. Other Common causes (20-25%)
    1. Coronavirus
    2. Parainfluenza virus
    3. Adenovirus
    4. Enterovirus
    5. Influenza
    6. Respiratory Syncytial Virus (RSV)
  4. Less Common causes (10-15%)
    1. Chlamydia pneumoniae
    2. Mycoplasma pneumoniae
    3. Group A Streptococcal Pharyngitis
  5. Rare Causes
    1. Mumps
    2. Rubella
    3. Rubeola
    4. Cytomegalovirus (CMV)
  • Differential Diagnosis
  1. Purulent Nasal Discharge more than 10-14 days
    1. Acute Sinusitis (especially if Maxillary Tooth Pain and unilateral sinus tenderness)
  2. Purulent cough, fever over 101, and acute debilitation
    1. Tracheobronchitis
    2. Pneumonia
    3. Influenza
  3. Laryngitis and non-productive cough more than 2 weeks
    1. Mycoplasma pneumoniae
    2. Chlamydia pneumoniae
  4. Raspy cough
    1. Pertussis (increasing Incidence in U.S.)
  5. Dysphagia, Drooling, Stridor and high fever
    1. Epiglottitis
  • Symptoms
  1. Nasal symptoms (precede other symptoms by 1-2 days)
    1. Sneezing
    2. Nasal congestion or stuffiness
    3. Nasal Discharge increased
  2. Sore Throat: mild "scratchy" Sensation
  3. Eye burning and eye tearing
  4. Dry, non-productive cough (40-60% of patients)
    1. Begins on days 2-3 and may persist for 7-10 days
  5. Generalized symptoms
    1. Malaise (mild)
    2. Muscle aches
    3. Low grade fever
  6. Less common symptoms
    1. Hoarseness
    2. Headache
    3. Chills
  • Signs
  1. Low-grade fever less than 101 F (38.5 C)
  2. Nose
    1. Clear Nasal Discharge
    2. Red, swollen nasal mucosa
  3. Throat with mild erythema
  • Complications (1-2%; higher risk in smoke exposure)
  • Management
  1. General
    1. Cold Preparations do not change course
      1. No study shows shortened symptom course
      2. No study shows reduced secondary complications
    2. Antibiotics not indicated
      1. Consider discussing contingency plans
        1. Lays out plan for when antibiotics indicated
        2. Eliminates pressure for antibiotic prescription
      2. Example
        1. If symptoms persist beyond 14 days then...
        2. Antibiotics indicated for Acute Sinusitis
      3. Consider Delayed Antibiotic Prescription
        1. Patient calls, picks up, or fills a prescription after a set time of persistent symptoms
        2. Reduces antibiotic use by 40%
        3. Little (2014) BMJ 348:g1606 [PubMed]
      4. Reference
        1. Mangione (2001) Arch Pediatr Adolesc Med 155:800 [PubMed]
    3. Avoid cough and Cold Preparations under age 4 years
      1. Symptomatic therapy with Analgesics (Acetaminophen and Ibuprofen) and Nasal Saline are preferred
      2. Cough and Cold Preparations top the list of toxic ingestions in this age group
      3. No evidence of benefit for cough and Cold Preparations in young children
      4. Leads to emergency visits, hospitalizations, and deaths
      5. FDA recommends not using cough and Cold Preparations under age 2 years
      6. De Sutter (2022) Cochrane Database Syst Rev (2):CD004976 +PMID: 22336807 [PubMed]
  2. Symptomatic therapy
    1. See Sore Throat symptomatic management
    2. Muscle aches, fever, chills
      1. Acetaminophen (do not exceed maximum dose)
      2. Ibuprofen (avoid in Dehydration)
    3. Hydration
      1. Maintain adequate hydration
      2. Avoid over-hydration in children due to risk of Hyponatremia
    4. Nasal symptoms
      1. Nasal Saline
        1. First-line, preferred, safe and effective Decongestant
      2. Decongestants reduce nasal congestion and discharge
        1. Topical Decongestants (e.g Afrin) for no more than 3 days (Rhinitis Medicamentosa risk)
          1. Avoid afrin (Oxymetazoline) in children ("One Pill Can Kill")
            1. Risk of central alpha-2 Agonist, Clonidine-like CNS depression
          2. Neo-Synephrine (Intranasal Phenylephrine) is preferred nasal Decongestant in children
        2. Oral Decongestants (e.g. Sudafed, Entex)
          1. Not routinely recommended (systemic effects including Blood Pressure increase)
          2. Pseudoephedrine (Sudafed) may offer benefit in some patients
          3. Phenylephrine orally (Sudafed PE) is ineffective due to reduced absorption
      3. Antihistamines are not effective in acute URI
        1. May also predispose to Acute Sinusitis complication (due to osteomeatal complex plugging)
        2. May be considered in combination with Decongestant if concurrent allergic symptoms
      4. Vaseline at opening of nares may reduce mucosal irritation and fissures
        1. Exercise caution in insertion to prevent aspiration
      5. Cool Mist Humidifier may loosen discharge (however, no evidence)
        1. Avoid warm mist humidifiers due to low efficacy and burn risk
    5. Cough
      1. Intranasal Ipratropium (intranasal Atrovent)
        1. May reduce persistent cough following URI (based on one small study)
          1. Holmes (2019) Respir Med 86(5): 425-9 [PubMed]
      2. Cough Suppressants (e.g. Dextromethorphan, Tessalon)
        1. No Cough Suppressant (including Codeine, Dextromethorphan) has been found effective for URI
        2. Avoid use overall as these are ineffective, and have adverse effects and abuse potential
        3. If used, limit use (e.g. cough interfering with sleep)
        4. Unsuppressed cough may prevent complications
        5. Codeine has found no more effective than Placebo in Cough Suppression
      3. Cough Expectorants
        1. Guaifenesin paradoxically may reduce cough in URI (variable efficacy)
        2. Dicpinigaitis (2003) Chest 124:2178-81 [PubMed]
    6. Wheezing with reactive airway disease (RAD) exacerbation
      1. Consider high dose Inhaled Corticosteroids (especially in children)
        1. However, Intranasal Corticosteroids are NOT effective in the Common Cold
        2. Budesonide (Pulmicort) MDI or nebulizer
        3. Beclomethasone MDI
  3. Alternative Medicine therapies that may be effective
    1. Adults
      1. Andrographis paniculata (Kalmcold) 200 mg daily for 5 days
        1. Hu (2018) PLOS ONE 13(11): e0207713 [PubMed]
      2. Zinc acetate or gluconate lozenges used during symptomatic URI period
    2. Children (use with caution especially under age 4 years)
      1. Honey once (do not use under age 1 year old, Infantile Botulism risk)
        1. Honey 2.5 ml (age 2-5 years), 5 ml (age 6-11 years) or 10 ml (age 12-18 years) once
      2. Zinc acetate or gluconate lozenges used during symptomatic URI period
      3. Vapor rub (camphor, Menthol, eucalyptus) once
  • Prevention
  1. Frequent Hand Washing or hand sanitizer to prevent spread of infection
    1. Single most effective strategy
  2. Probiotic milk (with live culture lactobacillus)
    1. May reduce respiratory infections in children age <7
    2. Hatakka (2001) BMJ 322:1-5 [PubMed]