What is the recommended treatment for respiratory syncytial virus (RSV) in infants, high‑risk patients, and elderly adults?

RSV Treatment

For RSV infection, treatment remains primarily supportive with hydration, supplemental oxygen, and mechanical ventilation when needed, as there is no definitive curative therapy currently available for active infection. 1, 2

Treatment by Population

Infants and High-Risk Children

Palivizumab (Synagis) is the only FDA-approved immunoprophylaxis for RSV disease prevention in specific high-risk pediatric populations, administered monthly during RSV season to premature infants and children under 24 months with chronic lung disease, cardiac disease, or other underlying medical conditions. 3, 2, 4

• Five monthly doses provide protective serum antibody concentrations throughout most of the RSV season, with trough concentrations 30 days after the fifth dose remaining well above protective levels. 5
• Palivizumab reduces RSV-related hospitalizations in high-risk infants but does not treat active infection—it is purely preventive. 2, 4
• Nirsevimab is a newer long-acting monoclonal antibody that provides protection through one RSV season with a single dose, eliminating the need for monthly injections. 5
• Infants aged 8-19 months at increased risk entering their second RSV season require another dose of nirsevimab. 5

Maternal Immunization for Infant Protection

Pregnant persons should receive one dose of RSVpreF (Abrysvo) between 32-36 weeks gestation during September-January to provide passive protection to infants through transplacental antibody transfer. 5

• Protection conferred through maternal vaccination likely wanes after 3 months, similar to influenza and COVID-19 vaccines given during pregnancy. 5
• At least 14 days are required after maternal vaccination for adequate antibody development and transplacental transfer. 5
• Infants who will be less than 8 months during RSV season may need nirsevimab if maternal antibodies have waned. 5

Antiviral Therapy (Limited Use)

Ribavirin is the only licensed antiviral treatment but has marginal clinical benefit and is generally reserved for immunocompromised patients with lower respiratory tract disease. 3, 2, 4

• Ribavirin is typically administered as a small particle aerosol, though oral and intravenous forms have been used mainly in immunocompromised patients. 3
• Use is limited due to issues with efficacy, safety, cost, and questionable adverse effect profiles. 1, 2
• Ribavirin administration is typically limited to children and infants in complicated cases. 1, 6

Supportive Care (Mainstay of Treatment)

All RSV patients require supportive therapy as the primary treatment approach, including:

• Hydration maintenance (oral or intravenous depending on severity). 1
• Supplemental oxygen for hypoxemia. 1, 2
• Mechanical ventilation in severe hospitalized cases with respiratory failure. 1
• Most RSV cases can be managed as outpatients with supportive care alone. 1

Therapies WITHOUT Proven Benefit

Bronchodilators, corticosteroids, and montelukast have not demonstrated conclusive clinical benefit in RSV treatment and are not routinely recommended. 4

Prevention in Adults (≥50 Years)

Vaccination Recommendations

All adults aged ≥75 years should receive a single lifetime dose of RSV vaccine regardless of comorbidities, due to significantly elevated rates of hospitalization, severe disease, and mortality. 5, 7, 8

Adults aged 60-74 years should receive RSV vaccination if they have any of the following risk factors:

• Chronic respiratory conditions (COPD, asthma, bronchiectasis, interstitial lung disease, chronic respiratory failure). 5, 7, 8
• Cardiovascular disease (heart failure, coronary artery disease, other chronic cardiovascular diseases). 5, 7, 8
• Diabetes mellitus, particularly with complications. 5, 7, 8
• Chronic kidney disease, especially end-stage renal disease. 5, 7, 8
• Chronic liver disease. 5, 7, 8
• Chronic neurological or neuromuscular diseases. 5, 7, 8
• Severe obesity (BMI ≥40 kg/m²). 7
• Moderate or severe immunocompromise (transplant recipients, malignancies, immunosuppressive medications, HIV). 5, 7, 8
• Residence in nursing homes or long-term care facilities. 5, 7
• Frailty or dementia. 5, 7

Adults aged 50-59 years with risk factors should receive RSVPreF3 (Arexvy), which is the only vaccine approved for this younger age group. 5, 8

Vaccine Administration Details

A single lifetime dose is recommended—no booster doses are currently indicated, as one dose provides protection for at least two consecutive RSV seasons. 5, 7, 8

• RSVPreF3 (Arexvy) maintains efficacy for at least three seasons with cumulative efficacy of 62.9% against RSV-associated lower respiratory tract disease. 7
• RSVpreF (Abrysvo) demonstrates sustained protection for at least two seasons with cumulative efficacy of 58.8-81.5% depending on symptom severity. 7

Administer between September and November (or August-October), before or early in the RSV season, to maximize protection during peak transmission months. 5, 7, 8

• RSV vaccine can be co-administered with seasonal influenza vaccine at different injection sites. 5, 7, 8
• Co-administration may result in numerically lower antibody titers for both RSV and influenza, though clinical significance remains unknown. 5

Important Clinical Considerations

Patient attestation alone is sufficient evidence of risk factors—extensive medical documentation should not be required, and vaccination should not be denied due to lack of formal records. 5, 7

Previous RSV infection does not confer long-lasting immunity and does not contraindicate vaccination, as reinfections are common due to short-lived immune responses. 5, 7

If vaccine supply is limited, prioritize in this order:

1. Adults aged ≥75 years
2. Adults aged ≥50 years with multiple comorbidities
3. Residents of long-term care facilities 5, 7, 8

Safety Considerations

Postlicensure surveillance has identified a potential increased risk of Guillain-Barré syndrome following protein subunit RSV vaccination (Arexvy and Abrysvo), which led to risk-based rather than universal recommendations for adults aged 60-74 years. 7

• The number of RSV-associated hospitalizations, ICU admissions, and deaths preventable per 1 million vaccine doses exceeds the estimated number of potential vaccine-attributable Guillain-Barré syndrome cases. 7
• For adults aged ≥75 years and those with multiple comorbidities, the benefits substantially outweigh potential harms. 7

Infection Control

Hand washing and maintaining social distancing are imperative to minimize RSV transmission, as individuals are infectious even before symptomatic presentation begins and remain infectious as long as they are shedding virus. 1