What is the treatment approach for viral vs bacterial upper respiratory infections (URIs)?

Treatment Approach for Viral vs Bacterial Upper Respiratory Infections

Antibiotics should be avoided for viral upper respiratory infections (URIs) as they are ineffective and contribute to antimicrobial resistance, while bacterial URIs require targeted antibiotic therapy based on the specific pathogen and infection site. 1, 2

Distinguishing Viral from Bacterial URIs

Viral URIs (Most Common)

• Most URIs are viral in origin, characterized by cough, sneezing, rhinorrhea, sore throat, and nasal congestion, typically peaking within 3 days and resolving within 10-14 days 2
• Nasal purulence or discolored nasal discharge alone does not indicate bacterial infection; it is a sign of inflammation and not specific for infection 2
• Viral URI symptoms typically follow a pattern with fever, myalgia, and pharyngitis usually resolving within 5 days, while nasal congestion and cough may persist into the second and third week 3

When to Suspect Bacterial Infection

• Bacterial sinusitis should be suspected only when symptoms persist for more than 10 days without clinical improvement, symptoms are severe (fever >39°C, purulent nasal discharge, or facial pain lasting >3 days), or symptoms worsen after an initial period of improvement ("double sickening") 1
• Group A streptococcal pharyngitis should be confirmed by testing when symptoms include fever, tonsillar exudate/swelling, swollen/tender anterior cervical nodes, and absence of cough 3
• Fewer than 2% of viral URIs are complicated by acute bacterial rhinosinusitis (ABRS) 1

Treatment for Viral URIs

First-Line Management

• Symptomatic relief with analgesics/antipyretics such as acetaminophen or ibuprofen for pain or fever 2, 4
• Nasal saline irrigation for cleansing and palliative effects 2
• Oral decongestants for symptomatic relief of congestion (avoid in patients with hypertension or anxiety) 2
• Most viral URIs are self-limited and resolve within 10-14 days without specific treatment 2, 5

What to Avoid

• Antibiotics should not be prescribed for viral URIs including common cold, influenza, and viral laryngitis 6
• The number needed to harm from adverse effects of antibiotics (8) is much lower than the number needed to treat for benefit (18) in acute rhinosinusitis, highlighting the importance of judicious antibiotic use 1

Treatment for Bacterial URIs

Acute Bacterial Rhinosinusitis

• Amoxicillin is the drug of choice for uncomplicated ABRS due to its effectiveness against Streptococcus pneumoniae 7, 8
• Amoxicillin-clavulanate is recommended when there is concern for beta-lactamase producing organisms like Haemophilus influenzae and Moraxella catarrhalis 1, 8
• For patients with penicillin allergy, doxycycline or a respiratory fluoroquinolone may be used as alternatives 1

Streptococcal Pharyngitis

• Confirm diagnosis with rapid antigen test (RAT) or throat culture before initiating antibiotics 1
• Penicillin V is the treatment of choice for confirmed streptococcal pharyngitis 1, 8
• Antibiotics should only be prescribed if test or culture results are positive for group A Streptococcus 6

Bacterial Bronchitis/Pneumonia

• For bacterial lower respiratory tract infections, amoxicillin (3 g/day) is the reference treatment for pneumococcal pneumonia in adults without risk factors 9
• For patients with risk factors or suspected atypical pathogens, treatment options include amoxicillin-clavulanate, parenteral 2nd or 3rd generation cephalosporins, and respiratory fluoroquinolones 9

Common Pitfalls and Caveats

• More than 80% of ambulatory care visits for sinusitis result in an antibiotic prescription, most of which are unnecessary 1
• Excessive antibiotic use is strongly associated with the development and spread of bacterial drug resistance 2
• Radiographic imaging is not recommended for patients who meet diagnostic criteria for acute rhinosinusitis unless a complication or alternative diagnosis is suspected 1
• Treating all bronchitis cases with antibiotics despite most being viral in origin should be avoided 9
• Using fluoroquinolones as first-line therapy when narrower-spectrum antibiotics would be appropriate should be avoided 9

Special Populations

• For children with URIs, stringent diagnostic criteria should be applied to distinguish viral from bacterial infections, and antibiotics should be reserved only for confirmed bacterial infections 3
• Acute otitis media can be managed without antibiotics except in children younger than 6 months, children ages 6 to 23 months with bilateral AOM, children older than 2 years with bilateral AOM and otorrhea, and certain high-risk patients 5
• Patients with underlying conditions, such as chronic respiratory conditions, may require closer monitoring and potentially different management approaches 2