Viral Infections

Varicella zoster virus 

Treatment is not routinely recommended in otherwise healthy children with varicella due to the self-resolving nature of infection and short window of viral replication (<72 hours from onset of rash)  

Consider treatment early in disease course in patients at increased risk for moderate to severe varicella based on one or more of the following criteria:  

Age> 12 years old not immunized against VZV 

Chronic cutaneous or pulmonary disorder 

Receiving long term salicylate therapy  

Receiving short or intermittent courses of  systemic corticosteroids 

See 2nd column for treatment indications 

Outpatient/enteral therapy for patients at increased risk:  

Acyclovir
20 mg/kg/dose (max 800 mg/dose) enterally four times daily 

OR 

Valacyclovir using dose below if patient is able to take pills 

IV therapy for patients requiring hospitalization due to varicella: 

Acyclovir
10 mg/kg/dose IV q8h 

ID consult recommended for patients hospitalized due to varicella or related complications  

Duration: 5 days for outpatient therapy, individualized based on response for hospitalized patients but usually 7-10 days similar to below for immuno-compromised patients 

Varicella zoster virus 

As with varicella there is a short window of viral replication (<72 hours from onset of rash); treatment is recommended if it can be initiated within this window or > 72 hours but patient presents with ongoing appearance of new lesions 

Valacyclovir
20 mg/kg/dose (max 1000 mg/dose) enterally tid 

(preferred if patient able to take pills) 

OR  

Acyclovir
20 mg/kg/dose (max 800 mg/dose) enterally four times daily 

(if patient unable to take pills or otherwise to access valacyclovir) 

Varicella zoster virus infection in immuno-compromised hosts 

Includes manifestations of varicella (primary infection) or herpes zoster (reactivation) 

Varicella zoster virus 

IV therapy: 

Acyclovir
10 mg/kg/dose IV q8h 

Enteral therapy:* 

Valacyclovir
20 mg/kg/dose (max 1000 mg/dose) enterally tid 

(preferred if patient able to take pills) 

OR  

Acyclovir
20 mg/kg/dose (max 800 mg/dose) enterally four times daily 

(if patient unable to take pills or otherwise to access valacyclovir) 

Consider ID consultation 

Duration: Antiviral therapy is typically given for 7-10 days or until lesions have crusted over  

*Therapy may be initiated enterally in  patients >= 2 yo with localized herpes zoster, without herpes zoster ophthalmicus or oticus, and without severe symptoms. For patients not meeting these criteria, initiation with IV therapy is recommended, with transition to enteral when the patient shows clinical improvement (no new lesions are appearing) 

Herpes simplex encephalitis or other disseminated disease regardless of immune status, including suspected HSV encephalitis pending diagnostic evaluation 

See guidance on HSV disease  in neonates and young infants < 3 months old 

Age 3 months to < 12 years: 

Acyclovir
15 mg/kg/dose IV q8h 

>=12 years: 

Acyclovir
10 mg/kg/dose IV q8h 

ID consult recommended 

Duration: 21 days 

Some experts may recommend suppressive oral acyclovir following acute treatment of HSV encephalitis in infants 3-12 months of age. Consult ID and refer to neonatal guidelines for suppressive dosing if recommended 

Acyclovir
20 mg/kg/dose (max 800 mg/dose) enterally tid 

OR 

Valacyclovir
20 mg/kg/dose (max 1000 mg/dose) enterally bid 

For patients unable to tolerate enteral therapy: 

Acyclovir
5 mg/kg/dose IV q8h 

Enteral therapy is preferred if possible. IV therapy increases risk for nephrotoxicity due to crystal nephropathy with greater risk associated with dehydration, higher dose and faster rate of infusion. If IV therapy is given, ensure good hydration status 

Transition to enteral therapy as soon as possible 

Episodic treatment most likely to be beneficial if initiated within 72 hours of onset 

Duration: Usually 5-7 days, dependent on clinical resolution; though may treat with single day (2 dose) duration with valacyclovir in adolescents 

Chronic suppressive therapy may be considered for patients experiencing 6+ outbreaks/year 

Initial IV therapy for patients at high risk for progression or with severe symptoms or impaired enteral intake: 

Acyclovir
10 mg/kg/dose IV q8h 

Transition to enteral therapy when patient shows clinical improvement and is able tolerate enteral treatment 

Enteral therapy for patients with mild-moderate symptoms, low risk for progression:  

Acyclovir
20 mg/kg/dose (max 800 mg/dose) enterally tid 

OR 

Valacyclovir
20 mg/kg/dose (max 1000 mg/dose) enterally bid 

Consider ID consult 

In immuno-compromised host, start treatment as soon as possible (based on clinical suspicion) and regardless of days elapsed since onset  

Duration: Until complete healing of the lesions, generally 7-14 days 

Herpes simplex genital infection in adolescents, first episode 

Valacyclovir
1000 mg enterally bid  

OR 

Acyclovir
800 mg enterally tid 

First reported episode of genital lesions is suggestive of primary infection, treatment is generally indicated and should be started as soon as possible and regardless of days elapsed since onset 

Duration: 7-10 days. Treatment can be extended until complete healing of lesions. Starting suppressive therapy may be considered after first episode, and is indicated starting at 36 weeks gestation in pregnant patients (see below) 

For patients who are pregnant and near delivery, further distinction of primary vs non primary infection should be made via lab testing to guide management of neonate, refer to published guidelines 

Herpes simplex genital infection in adolescents, prevention or treatment of recurrent episodes 

Suppressive therapy, non-pregnant patient: 

Acyclovir
400 mg enterally bid 

OR  

Valacyclovir
1000 mg enterally daily 

Suppressive therapy,  pregnant patient: 

Acyclovir
400 mg enterally tid 

OR  

Valacyclovir
1000 mg enterally daily 

Episodic therapy for non-primary infection:  

Acyclovir
800 mg enterally tid  

OR 

Valacyclovir
1000 mg/dose enterally daily  

Duration: 

Suppressive therapy for 6-12 months following first episode may prevent recurrence and improve quality of life, and decrease risk of transmission to sexual partners.  

Suppressive therapy is also indicated for pregnant patients with history of genital HSV beginning at 36 weeks gestation. 

Alternatively, episodic treatment of recurrent episodes may be used. Initiate therapy within 1 day of lesion onset or during prodrome for 5 days 

Influenza 

See detailed Influenza Guidelines including treatment indications 

Oseltamivir according to body weight: 

Preterm infants:  

<38 weeks corrected gestational age: 1 mg/kg/dose enterally bid 

38-40 weeks corrected gestational age: 1.5 mg/kg/dose enterally bid 

>40 weeks corrected gestational age: same as term infant dosing 

Contact Pediatric ID/ASP for infants with corrected gestational age < 28 weeks 

Term infants 0-8 months: 

3 mg/kg/dose enterally bid 

Infants 9-11 months: 

3.5 mg/kg/dose enterally bid 

Children >=12 months: 

<=15kg: 30 mg/dose enterally bid 

>15-23kg: 45 mg/dose enterally bid 

>23-40kg: 60 mg/dose enterally bid 

>40kg: 75 mg/dose enterally bid 

Duration: 5 days for most patients* 

*For patients with critical illness or significant immunocompromise, longer courses may be considered based on severity of illness. Please consult ID for assistance in these cases. 

Oseltamivir Dosing for Prophylaxis (most effective if initiated within 48-72 hours of exposure:  

Age < 3 months: not recommended 

Infants 3-8 months: 

3 mg/kg/dose enterally daily 

Infants 9-11 months: 

3.5 mg/kg/dose enterally daily 

Children >= 12 months:  

<=15kg: 30 mg/dose enterally daily 

>15-23kg: 45 mg/dose enterally daily 

>23-40kg: 60 mg/dose enterally daily 

>40kg: 75 mg/dose enterally daily 

Duration: 7 days 

No specific therapy

Coronavirus disease 2019 (COVID-19), mild-moderate  

Mild: No new or increased supplemental oxygen requirement, with symptoms limited to upper respiratory tract 

Moderate: No new or increased supplemental oxygen requirement, with symptoms involving the lower respiratory tract, or radiographic findings on chest X-ray 

Supportive care is recommended for most patients

Inpatient antiviral therapy may be considered on a case-by-case basis. 

Outpatient therapy may be considered for high risk patients if indicated per Emergency Use Authorization, please refer to PIDS guidelines

See severe-critical section below if treating with antiviral therapy 

Coronavirus disease 2019 (COVID-19), severe-critical 

Severe: new or increased requirement for supplemental oxygen 

Critical: new or increased requirement for invasive or noninvasive mechanical ventilation, sepsis, multiorgan failure, or rapidly worsening clinical trajectory that does not yet meet these criteria 

Remdesivir:

Age <12 years and/or weight < 40 kg: 
Remdesivir  lyophilized powder only 

Weight 3.5-40 kg:
5 mg/kg/dose IV on day 1, then 2.5 mg/kg/dose IV q24h 

Age ≥12 years and weight >40 kg: 
Remdesivir injection solution or lyophilized powder 

Weight >40 kg:
200 mg/dose IV on day 1, then 100 mg/dose IV q24h 

See 4th column for monitoring, last column for duration 

AND 

Dexamethasone*
0.15 mg/kg/dose (max 6mg/dose) IV or enterally q24h (see last column for duration)  

For patients especially adolescents with substantially escalating respiratory support needs (requiring critical care) after initiation of remdesivir and dexamethasone, consider adding IL-6 inhibitor or JAK inhibitor in consultation with ID. There is not yet sufficient data to recommend routinely adding these medications in pediatric patients.

Use the age-appropriate remdesivir order panel to ensure adherence to criteria.  

Monitoring for remdesivir:  
 
Monitor hepatic panel at baseline and during therapy 

ALT >10 times the upper limit of normal and asymptomatic: Consider discontinuing remdesivir. 

ALT elevation AND signs or symptoms of liver inflammation: Discontinue remdesivir. 

Although the manufacturer's labeling recommends against use in patients with eGFR <30 mL/minute, significant toxicity with a short duration of therapy (e.g., 5 to 10 days) is unlikely.  

ID approval is required for  baricitinib use but not remdesivir use

Duration:  
Remdesivir: 
Severe disease: 5 days 

Critical disease: 5-10 days, guided by clinical course 

Dexamethasone:  
Up to 10 days or until hospital discharge, whichever comes first   

*Consider risks vs. benefits of dexamethasone in relationship to underlying conditions (e.g. prior immunosuppression, metabolic disease, etc.) especially in patients with less severe respiratory illness e.g. not requiring mechanical ventilation.  

Multisystem inflammatory syndrome in children (MIS-C) 

Rheumatology consult recommended 

Consider ID consult if needed to distinguish other etiologies if MIS-C diagnosis is not clearly established