Public health impact of the adjuvanted RSVPreF3 vaccine in adults aged 60 years and older: results from a modeling study in six Latin American countries.

Background: Respiratory syncytial virus (RSV) can cause acute respiratory infection (ARI) and severe symptoms in older adults. The adjuvanted RSV prefusion F protein vaccine (adjuvanted RSVPreF3) offers protection to adults against RSV ARI and RSV lower respiratory tract disease (LRTD). We modeled the RSV burden and the public health impact of RSV vaccination in adults ≥60 years in six Latin American countries.

Research design and methods: A Markov model was adapted to the settings of Argentina, Brazil, Chile, Colombia, Mexico, and Panama. RSV ARI cases, hospitalizations, pneumonia cases, and deaths related to LRTD episodes were computed over a 5-year time horizon. Benefits of vaccination were calculated through incremental differences for coverage rates of 30% and 70% versus no vaccination. Uncertainty in key inputs was explored using one-way sensitivity analysis.

Results: Among adults ≥60 years, 22.3 million RSV ARI cases, ~936,000 RSV LRTD hospitalizations, ~862,000 pneumonia, and ~89,000 deaths were projected across the six countries, over 5 years. Assuming a 30% coverage, adjuvanted RSVPreF3 vaccination would prevent 2.6 million RSV ARI cases, 140,138 hospitalizations, 128,996 pneumonia cases, and 13,315 deaths.

Conclusion: Our results showed a substantial burden of RSV in Latin America that could be greatly alleviated through adjuvanted RSVPreF3 vaccination of adults ≥60 years.