How is respiratory syncytial virus (RSV) infection diagnosed and managed, and which patients should receive palivizumab prophylaxis?

RSV Infection: Diagnosis, Management, and Palivizumab Prophylaxis

Diagnosis of RSV Infection

RSV diagnosis is primarily clinical in most cases, with laboratory testing reserved for specific high-risk situations. 1, 2

When to test for RSV:

• Febrile infants ≤60 days old being evaluated for serious bacterial infection (a positive RSV test reduces but does not eliminate the risk of concurrent bacterial infection) 2
• Immunocompromised patients, transplant recipients, and those with severe underlying cardiopulmonary disease requiring risk stratification 2
• Infants receiving palivizumab prophylaxis who develop bronchiolitis (to determine if breakthrough RSV infection occurred, which warrants discontinuation of further prophylaxis) 2
• Hospitalized patients where cohorting or infection control measures are needed 2

When NOT to test:

• Routine outpatient bronchiolitis cases where management will be supportive regardless 2

Management of RSV Infection

Supportive care is the cornerstone of RSV management, as no antiviral therapy has proven effective for routine use. 1, 2, 3

Oxygen and Respiratory Support

• Administer supplemental oxygen when SpO2 falls below 90-92% via nasal cannula, head box, or face mask 1
• Continuously monitor oxygen saturation targeting >92% 1
• Escalate to high-flow nasal oxygen (HFNO) as first-line therapy when standard oxygen supplementation fails 1
• Prepare for immediate intubation when: SpO2 cannot be maintained >92% despite FiO2 >60%, recurrent apnea occurs, or signs of respiratory failure develop 1

Hydration and Supportive Measures

• Maintain hydration via nasogastric or intravenous routes if the child cannot maintain oral intake 1, 2
• Perform gentle nasopharyngeal suctioning only when nasal secretions obstruct breathing 1
• Elevate head of bed 30-45 degrees 1
• Use acetaminophen or ibuprofen for fever management 1, 2

What NOT to Do

These interventions have no benefit for mortality, morbidity, or quality of life:

• Do NOT use bronchodilators routinely for RSV bronchiolitis 1, 2
• Do NOT use corticosteroids 1, 2
• Do NOT prescribe antibiotics unless documented bacterial co-infection exists 1, 2
• Do NOT use palivizumab for treatment of established RSV infection—it is only approved for prevention 2, 3
• Do NOT use ribavirin routinely in children with RSV bronchiolitis 2

Special Population: Immunocompromised Patients

For hematopoietic stem cell transplant (HSCT) recipients and profoundly immunocompromised patients with RSV lower respiratory tract infection, ribavirin therapy should be considered. 4, 2

Ribavirin administration options:

• Aerosolized ribavirin: 2 g over 2 hours every 8 hours, or 6 g continuously over 18 hours per day for 7-10 days 2
• Systemic ribavirin: Day 1: 600 mg loading dose, then 200 mg every 8 hours; Day 2: 400 mg every 8 hours; Day 3 onward: increase to maximum 10 mg/kg every 8 hours 2
• For creatinine clearance 30-50 mL/min: maximum 200 mg every 8 hours 2

Combination therapy: Consider adding IVIG or anti-RSV-enriched antibody preparations for allogeneic HSCT patients with RSV lower respiratory tract disease 4, 2

Timing considerations: Defer conditioning therapy for patients with RSV infection planned for allogeneic HSCT, and consider deferring chemotherapy for patients scheduled for hemato-oncological treatment 2

Hospitalization Criteria

Admit patients with:

• Hypoxemia (SpO2 persistently <90%) 2, 3
• Signs of severe respiratory distress 2, 3
• Inability to maintain adequate oral intake 2, 3
• Underlying high-risk conditions (prematurity, chronic lung disease, congenital heart disease, immunocompromised status) 2, 3

Discharge Criteria

Patients are ready for discharge when:

• Oxygen saturation consistently >90% in room air for at least 12-24 hours 2
• Clinical improvement with better activity level, improved appetite, and decreased or absent fever for at least 12-24 hours 2
• Normal or baseline mental status 2
• Absence of substantially increased work of breathing, sustained tachypnea, or tachycardia 2

Palivizumab Prophylaxis

Palivizumab is indicated ONLY for prevention in specific high-risk populations, NOT for treatment of established RSV infection. 4, 2, 3

Who Should Receive Palivizumab

Infants born at ≤28 weeks gestational age:

• Eligible if younger than 12 months at the start of RSV season 4, 2
• May receive prophylaxis during their first RSV season, whenever that occurs during the first 12 months of life 2

Infants born at 29-31 weeks gestational age:

• May benefit from prophylaxis up to 6 months of age 2
• Available data for infants born at ≥29 weeks do not identify a clear gestational age cutoff for which benefits are clear 4

Infants with chronic lung disease (CLD)/bronchopulmonary dysplasia (BPD):

• Eligible if they require medical support (chronic corticosteroid therapy, diuretic therapy, or supplemental oxygen) within 6 months before the start of RSV season 4, 2
• During the second year of life, prophylaxis is recommended ONLY for infants who continue to require medical support during the 6-month period before the start of the second RSV season 4

Children ≤12 months with hemodynamically significant congenital heart disease (CHD):

• Infants with acyanotic heart disease receiving medication to control congestive heart failure who will require cardiac surgical procedures 4
• Infants with moderate to severe pulmonary hypertension 4
• Decisions for infants with cyanotic heart defects should be made in consultation with a pediatric cardiologist 4

Other high-risk populations to consider:

• Children <24 months who are profoundly immunocompromised during RSV season 4
• Children <2 years who undergo cardiac transplantation during RSV season 4

Who Should NOT Receive Palivizumab

Prophylaxis is NOT recommended for:

• Infants with hemodynamically insignificant heart disease (e.g., secundum atrial septal defect) 4
• Children with Down syndrome unless they have qualifying heart disease, CLD, airway clearance issues, or prematurity (<29 weeks gestation) 4
• Patients with cystic fibrosis unless other indications are present (an infant with cystic fibrosis with clinical evidence of CLD and/or nutritional compromise in the first year of life may be considered) 4
• Most children in the second year of life (RSV hospitalization rates in the second year are less than half the rate in low-risk infants during the first five months of life) 2

Palivizumab Dosing and Administration

Dosing regimen: 15 mg/kg intramuscularly monthly throughout RSV season, maximum of 5 doses per season 2

Special considerations:

• After cardiac bypass or extracorporeal membrane oxygenation, a post-operative dose of palivizumab (15 mg/kg) should be considered because a mean decrease in palivizumab serum concentration of 58% was observed after cardiopulmonary bypass 4

Discontinuation: If any infant receiving monthly palivizumab prophylaxis experiences a breakthrough RSV hospitalization, monthly prophylaxis should be discontinued because of the extremely low likelihood of a second RSV hospitalization in the same season (<0.5%) 4

Efficacy of Palivizumab

Palivizumab reduces RSV hospitalization by 45-55% in high-risk populations (10.6% placebo vs 4.8% palivizumab in the IMpact-RSV trial). 2, 5, 6

• In premature infants without BPD: 78% reduction in RSV hospitalization (8.1% vs 1.8%) 5
• In children with BPD: 39% reduction (12.8% vs 7.9%) 5

Important limitation: Despite this benefit, palivizumab has minimal effect on the overall RSV disease burden because the majority of RSV hospitalizations occur in healthy term infants who are not eligible for prophylaxis. 2

Infection Control Measures

Hand hygiene is the single most important measure to prevent RSV transmission. 2

Essential infection control practices:

• Hand decontamination before and after direct patient contact using alcohol-based rubs (preferred when hands are not visibly soiled) 2
• Wear gowns for direct patient contact 2
• Use gloves with frequent changes to avoid spreading organisms on contaminated gloves 2
• Implement contact and droplet precautions throughout hospitalization for all RSV-positive patients 2
• Restrict healthcare personnel with upper respiratory infections from caring for high-risk patients 2
• Do not allow persons with respiratory infection symptoms to visit pediatric, immunosuppressed, or cardiac patients 2

Duration of isolation: Patients with RSV infection should remain in isolation precautions for the duration of their hospitalization or until symptoms resolve, as RSV viral shedding typically continues throughout the acute illness and can persist for 1-3 weeks in infants and young children. 2

Prevention Strategies for All Infants

Universal measures to reduce RSV risk:

• Avoid tobacco smoke exposure completely 2
• Limit exposure to crowds and group childcare during RSV season (November through March in most regions) 2
• Keep infants away from sick contacts 2
• Encourage breastfeeding to potentially decrease the risk of lower respiratory tract disease 4, 2
• Ensure influenza vaccination for the infant (starting at 6 months) and all household contacts 2