CDC’s annual respiratory disease season outlook predicts similar peak hospitalization rates for COVID-19, influenza and RSV — but a higher hospitalization rate for COVID-19 if a new variant emerges.
The US CDC released its 2025-2026 Respiratory Disease Season Outlook (Aug 25) and is predicting a similar number of combined peak hospitalizations due to COVID-19, influenza, and RSV compared to last season, but higher peak hospitalization rates for COVID-19 if a new variant emerges.
According to the agency, the combined peak hospitalization rate will be similar (within 20%) to the 2024-25 season, citing evidence that the magnitude of combined peak hospitalizations has been relatively consistent in the past three years.
However, the CDC raised the possibility of higher combined peak rate, which could be driven by the following factors:
- Emergence of a new SARS-CoV-2 variant with an increased ability to evade the body’s prior immunity, or a new variant associated with higher clinical severity
- Predominance of an influenza subtype with more severe outcomes
- Lower vaccine uptake or effectiveness, including:
- Lower than expected uptake of the COVID-19 vaccine, influenza seasonal vaccine, or RSV immunizations
- Lower effectiveness against COVID-19-, influenza-, or RSV-associated hospitalizations than for the 2024-2025 immunizations
COVID-19 Outlook
- Higher hospitalization risk — CDC projects that COVID-19 hospitalizations in the 2025-2026 season may equal or exceed last year’s peak, with the highest burden expected in January.
- Variant uncertainty — The emergence of a variant with moderate immune escape could drive peak weekly hospitalization rates as high as 6.7–9.5 per 100,000, compared to 3.8–5.9 without such a variant.
- Key drivers — Seasonal hospitalization trends will depend on summer 2025 activity, the appearance of new variants, and vaccination uptake and effectiveness, with waning immunity likely increasing risk.
Influenza Outlook
- Moderate severity expected — CDC projects a moderate influenza season overall, based on peak weekly hospitalizations, though some age groups could still experience high severity.
- Historical context — Last year (2024–2025) was classified as high severity across all ages — the first since 2017–2018. Back-to-back high-severity seasons have never been recorded since CDC began quantitative assessments in 2003–2004.
- Role of vaccination — Vaccination remains the most important factor for reducing burden. In 2024–2025, flu vaccines prevented an estimated 240,000 hospitalizations, mostly among adults ≥65 years. Vaccine uptake and effectiveness this season remain uncertain.
RSV Outlook
- Hospitalization rates steady — CDC projects RSV peak weekly hospitalization rates will be within 20% of last season’s, with moderate confidence.
- Infant protection — Pediatric RSV immunizations (maternal vaccination and monoclonal antibodies) continue to significantly reduce infant hospitalizations, with effectiveness expected to remain stable this season.
- Adult vaccination impact — Coverage among adults ≥75 years rose from 28.8% to 47.5% last season, and vaccines have proven effective against RSV hospitalizations, though protection may wane over time.
