What is the treatment for a 9-year-old with influenza (flu)?

Treatment of Influenza in a 9-Year-Old Child

For a 9-year-old child with influenza, oral oseltamivir is the first-line antiviral treatment, dosed at 60 mg twice daily for 5 days if the child weighs >23-40 kg, or 75 mg twice daily if >40 kg, ideally initiated within 48 hours of symptom onset. 1

Antiviral Treatment Approach

When to Treat with Antivirals

Antiviral therapy should be offered as early as possible for:

• Any child hospitalized with suspected influenza 1
• Children with severe, complicated, or progressive illness, regardless of symptom duration 1
• Children at high risk of complications (asthma, diabetes, immunosuppression, neurologic disorders) 1

Treatment may be considered for:

• Otherwise healthy children with influenza when initiated within 48 hours of illness onset, though greatest benefit occurs when started within 24 hours 1, 2
• Children whose household contacts are at high risk (siblings <6 months old or with underlying conditions) 1

Oseltamivir Dosing for 9-Year-Olds

Weight-based dosing for treatment (5-day course, twice daily): 1

• ≤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

Oseltamivir is available as capsules (30,45,75 mg) and oral suspension (6 mg/mL concentration). 1 The medication can be given with or without food, though administration with meals may improve gastrointestinal tolerability. 1

Alternative Antiviral Options

Zanamivir (inhaled) is an acceptable alternative for children ≥7 years without chronic respiratory disease: 10 mg (two 5-mg inhalations) twice daily for 5 days. 1 However, it is more difficult to administer than oral oseltamivir. 1

Peramivir (IV) is approved for children 2-12 years as a single 12 mg/kg dose (maximum 600 mg) given over 15-30 minutes, but only for acute uncomplicated influenza in non-hospitalized patients symptomatic ≤2 days. 1, 3 Its efficacy in hospitalized patients with serious influenza has not been established. 1, 3

Baloxavir is approved only for children ≥12 years weighing >40 kg. 1

Supportive Care Management

Fever Management

Antipyretics should be used to improve overall comfort rather than normalize temperature. 4 Fever itself is a beneficial physiologic response and does not worsen illness course or cause neurologic complications. 4

• Acetaminophen or ibuprofen are equally safe and effective as single agents 4
• Combined use of both agents provides approximately 2.5-4.4 additional hours without fever over 24 hours compared to single agents, but increases complexity and risk of inadvertently exceeding maximum doses 5
• Avoid tepid sponging as it causes discomfort without lasting benefit 6

Hydration and General Care

• Encourage adequate oral fluid intake to maintain hydration 1
• Monitor for signs of respiratory distress including increased respiratory rate, retractions, or hypoxia 1
• Ensure appropriate rest and minimize activity during acute illness 1

When to Consider Hospitalization

Children should be evaluated for hospital admission if they have: 1

• Oxygen saturation ≤92% on room air
• Respiratory rate >40/min (>50/min in infants)
• Signs of respiratory distress (grunting, intercostal retractions)
• Inability to maintain oral intake
• Severe dehydration
• Altered mental status

Antibiotic Considerations

Antibiotics are NOT routinely indicated for uncomplicated influenza. 1 However, consider antibiotics if:

• Secondary bacterial pneumonia is suspected (persistent or worsening fever after initial improvement, new respiratory symptoms) 1, 7
• Child is at high risk of complications or requires hospitalization 1

For children <12 years, co-amoxiclav is the antibiotic of choice to cover S. pneumoniae, S. aureus (including MRSA consideration), and H. influenzae. 1, 7 Use clarithromycin or cefuroxime for penicillin allergy. 1

Critical Pitfalls to Avoid

• Do not delay antiviral treatment while awaiting laboratory confirmation - treat based on clinical suspicion during influenza season 1
• Do not rely on rapid antigen tests to rule out influenza - they have low sensitivity and negative results should not guide treatment decisions 1
• Do not use amantadine or rimantadine - widespread resistance makes these ineffective 1
• Do not withhold treatment beyond 48 hours in severely ill children - oseltamivir may still provide benefit if symptomatic <6 days in hospitalized patients 1
• Monitor for neuropsychiatric events (delirium, abnormal behavior) which have been reported with neuraminidase inhibitors, though causality is uncertain 3