Respiratory Syncytial Virus (RSV) is a common virus that causes respiratory tract infections, affecting nearly all children by age two. While often presenting as a mild cold in healthy adults, RSV can cause severe illness in vulnerable populations, including infants, young children, and adults over 65. The virus is a leading cause of hospitalization in infants in the United States, often causing lung infections like bronchiolitis and pneumonia. For the average patient with an active infection, a routine, highly effective oral or intravenous antiviral medication is not a standard part of care.
Current Antiviral Treatment Options
Only one antiviral medication is approved for treating active RSV infection, but its use is severely restricted to a small subset of patients. This drug inhibits the virus’s ability to replicate and is typically delivered in an aerosolized form, requiring a specialized system for the patient to inhale. The administration process is complex, often lasting many hours a day for multiple days, and carries risks to both the patient and healthcare workers due to airborne exposure.
The limitations of this antiviral extend beyond its difficult delivery method. Concerns regarding its effectiveness in otherwise healthy individuals, its high expense, and potential side effects have prevented its widespread adoption. Its use is almost entirely reserved for patients with severe, life-threatening RSV disease who are also in a high-risk group. This includes severely immunocompromised individuals, such as bone marrow or lung transplant recipients, whose natural ability to fight the virus is compromised.
For the majority of patients with RSV, including those hospitalized, the risks and logistical challenges of this antiviral do not justify its use. Medical intervention for most active cases focuses on managing symptoms and supporting the body’s natural recovery process.
Standard Care for Managing Active Infection
Since a specific antiviral is rarely used, supportive care is the core strategy for managing an active RSV infection. For mild cases, management occurs at home and focuses on keeping the patient comfortable and ensuring adequate fluid intake. Using an over-the-counter pain reliever, such as acetaminophen, can help control fever and discomfort.
Maintaining hydration is a primary concern, especially for infants who may have difficulty feeding due to respiratory distress and nasal congestion. Caregivers are advised to use nasal saline drops followed by gentle suctioning to clear the nasal passages, which makes breathing and feeding easier. A cool-mist humidifier can also help to moisten the air and ease congestion and coughing.
Hospitalization becomes necessary if a patient, particularly an infant, shows signs of severe respiratory distress. These signs include difficulty breathing, decreased oxygen saturation, or an inability to take in fluids, leading to dehydration. In a hospital setting, care remains supportive but involves more intensive medical interventions.
Patients may receive supplemental oxygen, often humidified and delivered through a mask or nasal tubes, to maintain safe oxygen levels. Intravenous (IV) fluids are administered to correct dehydration when patients cannot drink enough. In the most severe instances, if the patient’s breathing muscles fatigue, mechanical ventilation may be required to support the lungs.
Preventive Strategies: Vaccines and Monoclonal Antibodies
A major shift in managing RSV has occurred with the development of effective tools for preventing severe disease before infection. These preventive measures fall into two categories: active immunization, which stimulates the body’s own immune system, and passive immunization, which delivers pre-made antibodies. Active immunization is accomplished through vaccines recommended for older adults and pregnant individuals.
Adults aged 60 and older can receive an RSV vaccine to generate a protective immune response. A vaccine is also available for pregnant individuals, typically administered between 32 and 36 weeks of gestation during RSV season. This maternal vaccination allows the mother’s antibodies to cross the placenta, protecting the newborn for their first six months of life when they are most susceptible to severe disease.
Passive immunization involves giving a monoclonal antibody injection directly to the infant. This protein is engineered to mimic the body’s natural antibodies. The newer, long-acting monoclonal antibody is recommended for all infants younger than eight months entering their first RSV season. This single dose provides immediate protection that lasts for the typical five-month duration of the RSV season.
This antibody is not a vaccine because it provides ready-to-use protection rather than prompting the baby’s immune system to produce its own defenses. This strategy is used for infants whose mothers did not receive the vaccine during pregnancy, or for high-risk infants up to 19 months old entering their second RSV season. These preventive injections are designed to block the virus from causing severe illness and are not used as a treatment once an active infection has begun.