Respiratory Syncytial Virus (RSV) is a common respiratory pathogen that circulates annually, often peaking in the fall and winter months. While it causes mild, cold-like symptoms in most healthy individuals, RSV can lead to severe lower respiratory tract illness in specific populations. It is the leading cause of hospitalization for infants under one year old and contributes to significant morbidity and mortality in older adults and those with chronic medical conditions. In the United States, RSV is estimated to cause between 58,000 and 80,000 hospitalizations in young children and 60,000 to 160,000 hospitalizations in seniors each year.
Daily Behavioral and Environmental Prevention
The virus spreads through respiratory droplets released when an infected person coughs or sneezes, or by touching a contaminated surface before touching the face. This contact transmission makes rigorous hand hygiene a foundational defense against RSV. Hands should be washed frequently with soap and water for at least 20 seconds, especially after coughing, sneezing, or being in a public place. If soap and water are unavailable, use an alcohol-based hand sanitizer containing at least 60% alcohol.
Since RSV can survive on hard surfaces like toys, doorknobs, and countertops for several hours, routine cleaning and disinfection of high-touch areas is important. Using an EPA-registered disinfectant effective against viruses reduces the risk of indirect transmission within a home or shared space. Reducing close contact with anyone showing cold-like symptoms, such as avoiding shaking hands or sharing utensils, also minimizes direct exposure to infectious droplets.
Minimizing time spent in crowded indoor settings reduces exposure, especially during peak RSV season. When gathering indoors, improving air circulation and ventilation introduces fresh air, which helps dilute the concentration of virus particles. This can be achieved by opening windows and doors when possible, or by using air purifiers with HEPA filters in enclosed spaces. If an individual is sick and must be around others, wearing a well-fitting face mask contains respiratory droplets and protects those nearby.
Understanding Available Immunization Tools
Recent advancements have introduced active and passive immunization options that offer targeted protection against severe RSV disease, primarily for the two most susceptible age groups. These strategies function through different mechanisms and are tailored to specific populations. Active immunization, such as the new RSV vaccines (Arexvy and Abrysvo), prompts a person’s own immune system to create protective antibodies.
Active vaccines are recommended for adults aged 60 and older, with a single dose generally providing protection for multiple seasons. The CDC also recommends vaccination for adults aged 50 to 74 who have underlying conditions that increase their risk of severe illness. These risk factors include chronic heart or lung disease, a weakened immune system, or severe diabetes. Since protection takes about two weeks to develop, vaccination is often advised in the late summer or early fall before the RSV season begins.
Abrysvo is also approved as a maternal vaccine for pregnant individuals to protect their newborn infants. It is typically administered during weeks 32 through 36 of pregnancy, allowing the mother’s antibodies to cross the placenta and provide the baby with protection during their first few months of life. This single dose is recommended during every pregnancy, as clinical trials showed it reduced the risk of severe RSV illness in infants by more than 50%.
For infants, a passive immunization strategy is available using a long-acting monoclonal antibody product, such as nirsevimab (Beyfortus). Unlike a vaccine, this antibody is injected directly into the baby’s bloodstream, offering immediate protection that lasts for about five months. This single-dose injection is recommended for all infants under eight months old who are born during or are entering their first RSV season. Infants born just before or early in the season should receive the dose within a week of birth, ideally before leaving the hospital.
The monoclonal antibody is also recommended for high-risk children between 8 and 19 months old who are entering their second RSV season. This includes children with chronic lung disease from prematurity or those who are severely immunocompromised. If a pregnant parent received the maternal vaccine, the infant usually does not need the monoclonal antibody, so parents should consult their healthcare provider. A separate monoclonal antibody, palivizumab (Synagis), requires monthly injections throughout the season and is reserved for the highest-risk infants, such as certain premature babies or those with specific heart conditions.
Tailored Protection for Vulnerable Populations
Protecting infants and older adults requires focused attention on limiting their exposure to the virus, given the severity of RSV in these groups. Caregivers of infants, particularly those under six months, should be cautious about who interacts closely with the baby. Family members or visitors showing signs of a cold or respiratory illness should avoid close contact, and parents may discourage visitors from kissing the baby’s face or hands.
If a household member develops a respiratory illness, isolation protocols should be implemented to protect vulnerable individuals. The sick person should limit time in shared spaces and maintain distance from the infant or high-risk adult. Frequent handwashing by all family members is important, and the sick person should consistently use a tissue to cover coughs and sneezes, disposing of it immediately.
Older adults, particularly those residing in nursing homes or long-term care facilities, are at increased risk for severe disease, and the virus can spread quickly in these settings. Caregivers and facility staff should maintain vigilance regarding symptom monitoring and ensure they are up-to-date on their own vaccinations to prevent transmission. For older adults with chronic conditions, proactive planning with a healthcare team to manage potential respiratory symptoms is prudent before the peak of the RSV season.