I have had a two‑week upper respiratory infection; what is the most likely cause and how should it be evaluated and managed?

Two-Week Upper Respiratory Infection: Likely Cause and Management

Most two-week upper respiratory infections are uncomplicated viral illnesses that do not require antibiotics and will resolve with symptomatic treatment alone. 1

Most Likely Cause

Your infection is almost certainly viral rhinosinusitis that is following its natural course. 2, 1 The key evidence supporting this:

• 90% of viral URIs resolve within 3 weeks, and cough/nasal drainage commonly persist for the full duration without indicating bacterial superinfection 1
• Studies show that 87% of adults with URI symptoms demonstrate sinus inflammation on CT scan, yet 79% show complete resolution within 2 weeks without antibiotics 2
• The typical progression shows fever resolving by day 5, sore throat by day 7, while cough and nasal drainage persist through day 10-14 in uncomplicated viral infections 2

When to Suspect Bacterial Sinusitis

Bacterial superinfection becomes likely only if symptoms persist beyond 10 days AND worsen, or if they worsen after initial improvement at 5-7 days. 2 Specifically, consider acute bacterial rhinosinusitis if you have:

• Symptoms lasting >10 days without improvement 2
• "Double worsening": initial improvement followed by worsening after 5-7 days 2
• Severe symptoms at onset: fever >39°C (102.2°F), facial swelling/erythema, or severe unilateral facial pain 2, 3

Importantly, colored nasal discharge alone does NOT indicate bacterial infection—mucopurulent secretions occur normally in viral infections due to neutrophil influx after a few days 2

Recommended Evaluation

No diagnostic testing is needed for uncomplicated viral URI at 2 weeks. 1 Specifically:

• No imaging required: CT or X-rays show abnormalities in most viral URIs and do not distinguish viral from bacterial infection 2
• No laboratory tests indicated: CBC, inflammatory markers, and cultures are not helpful in routine cases 1
• Clinical assessment only: History and physical examination are sufficient 1

Management Approach

Symptomatic treatment with reassurance is the only recommended intervention. 1

What TO Use:

• Honey and lemon for cough—as effective as pharmacological treatments 1
• Acetaminophen or ibuprofen for pain/fever 4
• Nasal saline irrigation for congestion 1

What NOT to Use:

• No antibiotics unless bacterial infection criteria above are met 1, 2
• No cough suppressants (including codeine)—they show no benefit over placebo 1
• No expectorants, mucolytics, antihistamines, or bronchodilators—no consistent evidence of benefit 1

Red Flags Requiring Re-evaluation

Return for assessment if you develop: 1, 3

• Symptoms persisting beyond 3 weeks (consider pertussis, atypical pneumonia, asthma, or GERD) 1
• High fever >39°C (102.2°F) 3
• Severe unilateral facial pain or facial swelling 2
• Shortness of breath or wheezing (may indicate undiagnosed asthma/COPD in up to 45% of patients with cough >2 weeks) 1
• Worsening after initial improvement 2

Common Pitfalls to Avoid

• Do not prescribe antibiotics reflexively at 2 weeks—this contributes to antimicrobial resistance without improving outcomes in viral infections 1
• Do not misinterpret colored mucus as bacterial infection—this is a normal viral URI finding 2
• Do not order imaging studies—they cannot distinguish viral from bacterial infection and show abnormalities in most viral cases 2