How long does the RSV (Respiratory Syncytial Virus) vaccine last?

From the Guidelines

The RSV vaccine provides protection against Respiratory Syncytial Virus (RSV) infection for a duration of approximately 6-12 months with a single dose administered intramuscularly 1.

Key Points

• The cumulative efficacy of the RSV vaccine over 2 seasons in adults ≥60 years old is around 67.2% (97.5% CI: 48.2,80.0) 1.
• The vaccine has been shown to be well tolerated in the overall population, with a clinically acceptable safety profile over 3 seasons 1.
• The exact duration of protection may vary depending on individual factors, such as age and underlying health conditions 1.

Duration of Protection

• A single dose of the RSV vaccine has demonstrated efficacy in preventing RSV-related lower respiratory tract infections for up to 150 days, with a median duration of protection of around 6 months.
• The cumulative efficacy over 3 seasons in adults ≥60 years old is around 62.9% (97.5% CI: 46.7,74.8) 1.

Safety and Efficacy

• The vaccine has been shown to be well tolerated in the overall population, with a clinically acceptable safety profile over 3 seasons 1.
• The estimated number of RSV-associated outcomes preventable per 1 million protein subunit RSV vaccine doses administered among adults aged ≥60 years is around 4,283 (range: 2,235–6,957) 1.

From the Research

RSV Vaccine Duration

The duration of the RSV vaccine's effectiveness is a crucial aspect of its application. According to the studies:

• Nirsevimab, a monoclonal antibody, has been shown to provide protection against RSV-associated lower respiratory tract infections for at least 150 days after administration 2.
• A real-world effectiveness study found that nirsevimab provided substantial protection against RSV-related outcomes for at least three months, with effectiveness declining over time but remaining significant at 55% at 14 weeks post-immunization 3.
• Another study found that the vaccine Abrysvo, approved for use in pregnancy to protect the newborn, has an efficacy of over 80% in the first 3 months of life but slightly decreases after an age of 6 months 4.
• The FDA-approved long-acting monoclonal antibody nirsevimab has been recommended for administration to all infants <8 months of age and for children 8 to 19 months of age who are at increased risk for severe RSV disease, indicating its potential for long-term protection 5.

Key Findings

Some key findings related to the duration of the RSV vaccine's effectiveness include:

• Nirsevimab's effectiveness against RSV infection was 68.4% (95% CI, 50.3%-80.8%) 3.
• The highest effectiveness of nirsevimab, 84.6% (95% CI, 58.7%-95.6%), was observed against severe RSV outcomes requiring ICU admission or high-flow oxygen 3.
• Abrysvo's efficacy decreases slightly after 6 months of age, but it remains an effective tool for preventing RSV-associated disease and complications in high-risk groups 4.

Effectiveness Over Time

The effectiveness of the RSV vaccine over time is an essential consideration. The studies suggest that:

• Nirsevimab's effectiveness declines over time but remains significant at 55% at 14 weeks post-immunization 3.
• Abrysvo's efficacy decreases slightly after 6 months of age, but its exact duration of protection is not specified 4.
• The long-acting monoclonal antibody nirsevimab has been recommended for administration to infants and young children, indicating its potential for long-term protection 5.