Indication	First Choice	Alternative	Comments/Special Issues
Primary Prophylaxis	Influenza vaccine	None	Note: See Figures 1 and 2 for detailed vaccines recommendations.
Primary Chemoprophylaxis Influenza A and B	Oseltamivir for 10 daysa Aged <3 months; not recommendedb Aged 3 months to <1 year; 3 mg/kg body weight/dose once dailyb Aged ≥1 to 12 years; weight-band dosingb ≤15 kg: 30 mg once-daily >15 kg to 23 kg: 45 mg once daily >23 kg to 40 kg: 60 mg once daily >40 kg: 75 mg once daily Aged ≥13 years; 75 mg once daily Zanamivir (aged ≥5 yr) for 10 days: 10 mg (2 inhalations) once dailyc	None	Primary chemoprophylaxis is indicated for unvaccinated HIV-infected children with moderate-to-severe immunosuppression (as assessed by immunologic and/or clinical diagnostic categories) who are household contacts or close contacts of individuals with confirmed or suspected influenza. Chemoprophylaxis of vaccinated HIV-infected children with severe immunosuppression also may be indicated based on health-care provider assessment of the exposure situation. Post-exposure antiviral chemoprophylaxis should be initiated as soon as possible after exposure. a Oseltamivir chemoprophylaxis duration: Recommended duration is 10 days when administered after a household exposure and 7 days after the most recent known exposure in other situations. For control of outbreaks in long-term care facilities and hospitals, CDC recommends antiviral chemoprophylaxis for a minimum of 2 weeks and up to 1 week after the most recent known case was identified (see http://www.cdc.gov/mmwr/preview/mmwrhtml/rr6001a1.htm). b Oseltamivir is approved by the FDA for treatment of influenza in children aged ≥2 weeks. It is not approved for prophylaxis in children aged <1 year. However, the CDC recommends that health-care providers who treat children ages ≥3 months to <1 year administer a chemoprophylaxis dose of 3 mg/kg body weight/dose once daily. Chemoprophylaxis for infants aged <3 months is not recommended unless the exposure situation is judged to be critical. Premature infants: Current weight-based dosing recommendations for oseltamivir are not appropriate for premature infants (i.e., gestational age at delivery <38 weeks). See J Infect Dis 202 [4]:563–566, 2010 for dosing recommendations in premature infants. Renal insufficiency: A reduction in dose of oseltamivir is recommended for patients with creatinine clearance <30 mL/min. c Zanamivir: Zanamivir is not recommended for chemoprophylaxis in children aged <5 years old.
Primary Chemoprophylaxis Influenza A (ONLY) Oseltamivir-resistant, adamantane-sensitive strains Based on CDC influenza surveillance; http://www.cdc.gov/flu/weekly/fluactivitysurv.htm	Amantadine or rimantadine for 10 daysd: Aged 1–9 years; 2.5 mg/kg body weight/dose twice daily (maximum dose of 150 mg/day) Aged ≥10 years <40 kg; 2.5 mg/kg body weight/dose twice daily ≥40 kg; 100 mg per dose twice daily (maximum dose of 200 mg/day)		d Adamantanes: Because of resistance in currently circulating influenza A virus strains, amantadine and rimantadine are not currently recommended for chemoprophylaxis or treatment (adamantanes are not active against influenza B virus). However, potential exists for emergence of oseltamivir-resistant, adamantane-sensitive circulating influenza A strains. Therefore, verification of antiviral sensitivity of circulating influenza A strains should be done using the CDC influenza surveillance website: http://www.cdc.gov/flu/weekly/fluactivitysurv.htm If administered based on CDC antiviral sensitivity surveillance data, both amantadine and rimantadine are recommended for chemoprophylaxis of influenza A in children aged ≥1 yr. For treatment, rimantadine is only approved for use in adolescents aged ≥13 years. Rimantadine is preferred over amantadine because of less frequent adverse events. Some pediatric influenza specialists may consider it appropriate for treatment of children aged >1 year. Renal insufficiency: A reduction in dose of amantadine is recommended for patients with creatinine clearance <30 mL/min.
Secondary Chemoprophylaxis	N/A	N/A	No role for secondary chemoprophylaxis
Treatment Influenza A and B	Oseltamivir for 5 dayse: Aged <3 months; 3 mg/kg/dose twice daily Aged 3 months to <1 year; 3 mg/kg/dose twice daily Aged ≥1 to 12 years; weight-band dosing ≤15 kg: 30 mg twice-daily >15 kg to 23 kg: 45 mg twice daily >23 kg to 40 kg: 60 mg twice daily >40 kg: 75 mg twice daily Aged ≥13 years; 75 mg twice daily Zanamivir (aged ≥7 years) for 5 days: 10 mg (2 inhalations) twice dailyf	None	e Oseltamivir is FDA-approved for treatment of influenza in children aged ≥2 weeks. The CDC recommends that clinicians who treat children ages ≥3 months to <1 year administer a dose of 3 mg/kg twice daily. A dose of 3 mg/kg/dose twice daily also is recommended for infants aged <3 months. Premature Infants: Current weight-based dosing recommendations for oseltamivir are not appropriate for premature infants: gestational age at delivery <38 weeks. See J Infect Dis 202 [4]:563–566, 2010 for dosing recommendations in premature infants. Oseltamivir treatment duration: Recommended duration for antiviral treatment is 5 days; longer treatment courses can be considered for patients who remain severely ill after 5 days of treatment. Renal insufficiency: A reduction in dose of oseltamivir is recommended for patients with creatinine clearance <30 mL/min. f Zanamivir: Zanamivir is not recommended for treatment in children aged <7 years.
Treatment Influenza A (ONLY) Oseltamivir-resistant, adamantane-sensitive strains Based on CDC influenza surveillance; http://www.cdc.gov/flu/weekly/fluactivitysurv.htm	Amantadine for 5 daysd: Aged 1–9 years; 2.5 mg/kg body weight/dose twice daily (maximum dose of 150 mg/day) Aged ≥10 years <40 kg: 2.5 mg/kg body weight/dose twice daily ≥40 kg: 100 mg per dose twice daily (maximum dose, 200 mg/day) Rimantadine for 5 daysd: Aged ≥13 years; 100 mg per dose twice daily (maximum dose of 200 mg/day)		Please see comment d, above, about adamantane use and resistance.

Key to Acronyms: CDC = Centers for Disease Control and Prevention; FDA = Food and Drug Administration