What is the optimal management regimen for an otherwise healthy adult or child with flu-like symptoms?

Ultimate Flu-Like Symptoms Management Regimen

Immediate Symptomatic Treatment

For otherwise healthy adults and children with flu-like symptoms, start with paracetamol (acetaminophen) or ibuprofen for fever, myalgias, and headache, combined with rest, abundant fluid intake, and avoidance of smoking. 1

Core Symptomatic Measures (All Patients)

• Antipyretics: Paracetamol or ibuprofen at appropriate doses for fever control (>38.5°C) and pain relief 1, 2
• Hydration: Ensure abundant oral fluid intake; consider IV fluids if severely ill or unable to maintain oral intake 3
• Rest: Complete rest during acute illness phase 1
• Smoking cessation: Strictly avoid smoking during illness 1
• Adjunctive measures: Consider short-course topical decongestants, throat lozenges, and saline nose drops 1

Critical Pediatric Considerations

Never give aspirin to children under 16 years due to Reye's syndrome risk. 1

• Children under 1 year and those at high risk must be assessed by a GP or emergency department 1
• Children aged 1-7 years should be seen by a nurse or GP 1
• Children 7+ years may be evaluated by community health team members 1
• All children require antipyretic and hydration counseling 1

Antiviral Therapy Decision Algorithm

When to Start Antivirals

Oseltamivir 75 mg twice daily for 5 days is the antiviral of choice and should be started immediately (without waiting for lab confirmation) if your relative meets ANY of these criteria: 1, 4, 5

High-Priority Indications (Start Immediately)

• Hospitalized with suspected influenza (any severity) 1
• Severe, complicated, or progressive illness attributable to influenza, regardless of symptom duration 1
• High-risk patients with suspected influenza of any severity 1, 5
• Pregnant women with suspected influenza 5
• Children under 5 years (especially under 2 years) with confirmed or suspected influenza 6, 1

Consider Antivirals For

• Otherwise healthy individuals if treatment can start within 48 hours of symptom onset (greatest benefit within 24 hours) 1, 7, 5
• Household contacts of high-risk individuals (children <6 months or those with underlying conditions) 1

Antiviral Dosing Specifics

Adults and adolescents: Oseltamivir 75 mg orally twice daily for 5 days 1, 4

• Reduce to 75 mg once daily if creatinine clearance <30 mL/min 1

Pediatric weight-based dosing (oseltamivir): 6, 4

• ≤15 kg: 30 mg twice daily

• 15-23 kg: 45 mg twice daily

• 23-40 kg: 60 mg twice daily

• 40 kg: 75 mg twice daily

Alternative: Inhaled zanamivir for patients ≥7 years without chronic respiratory disease 1, 8

Expected Antiviral Response

Patients should begin improving within 48 hours of starting antivirals; failure to improve warrants re-consultation and consideration of alternative diagnoses or complications 1

Antibiotic Therapy (Only When Indicated)

Do NOT routinely prescribe antibiotics for uncomplicated influenza. 1

When Antibiotics ARE Indicated

Use antibiotics only if bacterial co-infection is suspected or confirmed: 1, 3, 6

Non-Severe Bacterial Co-Infection

• First-line (oral): Co-amoxiclav or tetracycline 1
• Penicillin allergy: Clarithromycin or respiratory fluoroquinolone (levofloxacin, moxifloxacin) 1
• Pediatric (<12 years): Co-amoxiclav; clarithromycin or cefuroxime if penicillin-allergic 3, 6

Severe Influenza-Related Pneumonia

• IV combination therapy: Co-amoxiclav or 2nd/3rd generation cephalosporin (cefuroxime/cefotaxime) PLUS macrolide (clarithromycin/erythromycin) 1
• Alternative: Respiratory fluoroquinolone plus broad-spectrum β-lactamase stable antibiotic 1
• Administer within 4 hours of admission 1

Red Flags Requiring Immediate Re-Consultation

Instruct your relative to seek immediate medical attention if ANY of these develop: 1

• Shortness of breath at rest or with minimal activity 1
• Painful or difficult breathing 1
• Coughing up bloody sputum 1
• Drowsiness, disorientation, or confusion 1
• Fever persisting 4-5 days without improvement or worsening 1
• Initial improvement followed by recurrent high fever 1
• No improvement 48 hours after starting antivirals 1
• Oxygen saturation <90% 1
• Inability to maintain oral intake 1

Pediatric-Specific Warning Signs

• Grunting, intercostal recession, or breathlessness with chest signs 3
• Cyanosis 3
• Severe dehydration 3
• Altered consciousness or complicated/prolonged seizure 3

Diagnostic Testing (When Needed)

For most outpatients, clinical diagnosis is sufficient and laboratory confirmation is unnecessary. 1, 7

When Testing IS Indicated

• Hospitalized patients with suspected influenza 7
• When confirmed diagnosis will change treatment decisions 7
• Severe or persistent symptoms (>6 months suggests alternative diagnosis) 6

Preferred Tests

• Rapid molecular assays (NAAT): Superior sensitivity (86-100%) vs rapid antigen tests (10-70%); results in <20 minutes 6, 9
• RT-PCR: Gold standard for severe cases 9
• Avoid rapid antigen tests due to poor sensitivity 6

Additional Testing for Hospitalized/Severe Cases

• Complete blood count with differential 3, 6
• Urea, creatinine, electrolytes 3
• Liver enzymes 3
• Blood culture (before antibiotics if bacterial infection suspected) 3, 6
• Chest X-ray if hypoxic, severely ill, or deteriorating 3
• Pulse oximetry 3

Common Pitfalls to Avoid

Do not delay antiviral treatment waiting for laboratory confirmation - start empirically based on clinical presentation during influenza season 1, 7, 5

Do not prescribe antibiotics "just in case" - this promotes resistance without benefit unless bacterial co-infection is genuinely suspected 1, 9

Do not assume all antivirals are equal - oseltamivir has the best evidence base and safety profile for most patients 1, 10

Do not give aspirin to children/adolescents under 16 - use paracetamol or ibuprofen only 1

Do not use zanamivir in patients with chronic respiratory disease - risk of life-threatening bronchospasm 8, 10

Risk Stratification

High-Risk Groups Requiring Aggressive Management 1, 5

• Pregnant women
• Children <5 years (especially <2 years)
• Adults ≥65 years
• Chronic cardiac or pulmonary disease (including asthma)
• Chronic renal, hepatic, or metabolic disorders
• Immunocompromised states
• Residents of long-term care facilities

Prophylaxis for Exposed Household Contacts

For asymptomatic household contacts at very high risk of hospitalization who have been exposed to confirmed influenza: 9

• Oseltamivir 75 mg once daily for 10 days (post-exposure) or up to 6 weeks (seasonal prophylaxis) 1, 9
• Baloxavir is an alternative option 9
• This is NOT a substitute for vaccination but an adjunct in high-risk situations 10

Antiviral Adverse Effects to Monitor

Oseltamivir: Nausea (10%), vomiting (8%), headache (2%); rare neuropsychiatric events (delirium, hallucinations, abnormal behavior) 4

Zanamivir: Bronchospasm risk (contraindicated in asthma/COPD), nausea, diarrhea; rare neuropsychiatric events 8

Both drugs carry small risks of serious skin reactions, seizures, and cardiac arrhythmias in post-marketing surveillance 4, 8