CDC’s Center for Forecasting and Outbreak Analytics expects the combined weekly peak of COVID-19, influenza and RSV hospitalizations this winter to land within 20% of last season’s. The outlook, dated Sept. 23, 2026, covers October through May and calls it a “similar combined number of peak hospitalizations,” stated with low to moderate confidence.
CDC stresses that the document is a baseline for planning, not a forecast, and that peaks for the three diseases may overlap or arrive more than once during the season.
The 16.6 benchmark from last winter
Last season’s combined peak is the yardstick. According to CDC’s evaluation of the 2025-26 outlook, the three viruses together peaked at 16.6 hospitalizations per 100,000 people in the week ending Jan. 3, 2026, down from 19.5 in the week ending Feb. 1, 2025. By simple arithmetic, a peak within 20% of 16.6 would run from roughly 13 to 20 per 100,000.
The same evaluation shows how the parts moved. COVID-19 peaked at 2.0 per 100,000, well below the 4.2 of the season before and below what the prior outlook expected. Influenza reached 13.3 in the week ending Dec. 27, 2025, in a season CDC classified as moderate overall. RSV peaked at 3.0 in the week ending Feb. 21, 2026, about 20% under the previous year’s 3.9.
COVID-19 scenarios: 1.4 to 2.5, or 2.8 to 6.7 per 100,000
For COVID-19 alone, the 2026-27 outlook expects a peak weekly rate similar to or lower than last season’s, with moderate confidence. Activity was elevated and rising nationally as of Sept. 18, while hospitalizations remained low.
The modeling splits into two scenarios. Scenario A assumes no new variant with moderate immune escape and puts the peak at 1.4 to 2.5 hospitalizations per 100,000, most likely in early to mid-January. Scenario B assumes a variant similar to XEC appears between Sept. 16 and Dec. 15, 2026, and puts the peak at 2.8 to 6.7 per 100,000, most likely in late January 2027. About two-thirds of the experts, 65%, judged such a variant unlikely this season, and intermediate outcomes are possible.
Influenza and RSV timing
CDC expects influenza severity to be moderate across all ages, again with low to moderate confidence. U.S. flu activity is low now, and Southern Hemisphere seasons have mostly peaked and are declining, though activity is rising in Australia. The outlook notes that those patterns do not always carry over to the Northern Hemisphere, and that national flu hospitalization peaks usually fall between December and February. Flu vaccines prevented an estimated 180,000 hospitalizations in 2024-25. Last season was rated moderate overall but high severity for children aged 0 to 17, a split that matters for pediatric wards even when the national total looks ordinary.
RSV is expected to peak within 20% of last season’s weekly hospitalization rate, with moderate confidence. Activity is very low in most areas today. RSV normally crests in late December or early January, yet last season’s peak came in the week ending Feb. 21, 2026, and CDC says a late peak could recur. It offers three possible reasons for the shift: high population immunity from post-pandemic transmission, changes tied to the infant immunization rollout, and factors not yet identified.
Infant protection is a measurable part of that picture. A CDC MMWR report led by Monica Patton and Heidi Moline found 2024-25 RSV hospitalization rates among infants 0 to 7 months were 43% lower in RSV-NET and 28% lower in the New Vaccine Surveillance Network than in pre-pandemic seasons. For adults, CDC recommends a single lifetime RSV vaccine dose for those 75 and older and for those 50 to 74 with high-risk conditions.
Expert elicitation, scenario modeling and upside risks
The estimate combines three inputs: structured judgments from 25 subject-matter experts, historical surveillance data and CDC’s COVID-19 scenario modeling. CDC describes expert elicitation as a process in which specialists give individual judgments, discuss them as a group and feed the results into modeling, with an assessment of confidence attached.
The outlook names three upside risks that would raise the peak: viruses that evade existing immunity, through a new SARS-CoV-2 variant or influenza antigenic drift; increased viral severity; and lower vaccine uptake or effectiveness for any of the three diseases. Hospital counts used for tracking come from RESP-NET, which covers acute care hospitals in select counties across 14 states, a population of more than 40.9 million people, about 12% of the country. Because the three peaks can fall in different weeks, the combined rate on any given date can sit well below the sum of each disease’s own high point. The COVID-19 piece carries its own caveat: NHSN hospitalization data may underestimate true burden.
This article was produced with the assistance of AI and reviewed by Morning Overview editors prior to publication.
More from Morning Overview
- The NSA says three phone features should be off whenever you aren’t using them
- Hurricane Hunter radar shows four warning signs that a tropical cyclone is about to strengthen, a University of Miami study found
- Tropical Storm Rachel is dumping up to 12 inches on four Mexican states on its way to major hurricane strength
- The FTC says Lens.com doubled the price shoppers saw in Google ads
