From the Guidelines
The RSV vaccine should preferably be administered between September and November to adults aged ≥50 years with risk factors and all persons aged ≥60 years, as this timing helps prevent severe RSV disease before the typical RSV season begins. This recommendation is based on the latest position paper from the Portuguese Society of Pulmonology and other medical societies, published in 2025 1. The vaccine can be co-administered with the influenza vaccine, making it convenient for patients to receive both vaccinations at the same time.
- Key factors to consider when determining the best time for RSV vaccination include:
- Age: adults aged ≥50 years with risk factors, such as chronic obstructive pulmonary disease, asthma, heart failure, and diabetes, should receive the vaccine, as well as all persons aged ≥60 years
- Risk factors: individuals with certain medical conditions, such as immunocompromise, frailty, dementia, and residence in a nursing home, should be prioritized for vaccination
- Timing: vaccination should occur between September and November to ensure immunity is established before peak RSV season
- Co-administration: the RSV vaccine can be given concurrently with the influenza vaccine, simplifying the vaccination process for patients. According to the latest guidelines, if the vaccine cannot be made available to the entire recommended population, it should be prioritized for individuals aged ≥75 years and those aged ≥50 years with risk factors 1.
From the FDA Drug Label
Your child should receive the first SYNAGIS injection before the RSV season starts to help prevent RSV infection. If the season has already started, your child should receive their first SYNAGIS injection as soon as possible to help protect them when exposure to the virus is more likely “RSV season” is the time of year when RSV infections most commonly happen, usually fall through spring, but it may begin earlier or last longer in certain areas. The best time to get RSV vaccination with Synagis is before the RSV season starts. If the season has already started, the vaccination should be given as soon as possible. The RSV season typically occurs from fall to spring, but the exact timing may vary by area. It's essential to consult with a healthcare provider to determine the best time for vaccination in your specific region 2.
From the Research
RSV Vaccination Timing
The best time to get RSV vaccination is during the RSV season, which typically occurs from October to July in the Northern Hemisphere and from April to October in the Southern Hemisphere.
- The American Academy of Pediatrics recommends that palivizumab be administered to high-risk infants, such as those with congenital heart disease or chronic lung disease, in a series of 5 monthly doses, starting at the beginning of the RSV season 3.
- A study published in the Journal of the Pediatric Infectious Diseases Society found that palivizumab was effective in reducing severe RSV outcomes in children with immunodeficiencies, but the evidence was limited and more research is needed to confirm these findings 4.
- Another study published in the Cochrane database of systematic reviews found that palivizumab reduced hospitalization due to RSV infection and resulted in little to no difference in mortality or adverse events in children at high risk of RSV infection 5.
High-Risk Groups
Certain groups of children are at higher risk of severe RSV disease and may benefit from palivizumab prophylaxis, including:
- Preterm infants (<29 and ≤31 weeks gestational age) 3
- Children with congenital heart disease or chronic lung disease 3, 5
- Immunocompromised children, such as those with primary or acquired immunodeficiencies 4
- Children with Down syndrome, pulmonary or neuromuscular disorders, or cystic fibrosis 3
Dosage and Administration
Palivizumab is typically administered intramuscularly at a dose of 15 mg/kg once a month, for a total of 5 monthly doses 3, 5.
- The first dose is usually given at the beginning of the RSV season, and subsequent doses are given at 1-month intervals 3.