Influenza hospitalizations in Colorado have reached unprecedented levels, with nearly 2,500 individuals admitted since October 2025. A significant surge has been noted following recent holiday celebrations, particularly during the week of Christmas, which recorded 791 flu-related hospitalizations. This figure marks the highest since the Colorado Department of Public Health and Environment (CDPHE) began tracking flu hospitalizations in 2004.
Influenza Surge Linked to Holiday Gatherings
Dr. Chris Post, a physician and medical director at AdventHealth Parker, attributes the spike in hospitalizations to increased social interactions during the holidays. “It’s always worse around the holidays, just because people are traveling, getting on planes, and seeing families,” he stated. This year, the flu season commenced approximately four weeks earlier than usual, a shift many residents have observed in the wake of holiday gatherings.
Colorado resident Sarah Sweer noted an increase in flu cases correlating with more people coming together. She shared, “I think because more people are gathering, but I do see an increase typically.” The influx of flu patients has also impacted hospital staff, with Dr. Post reporting a notable number of healthcare workers out sick in recent weeks.
Flu Strain and Vaccine Effectiveness
This year’s dominant flu strain presents unique challenges, with symptoms lasting longer than in previous years. Dr. Post explained that this may result in the flu vaccine being less effective than in prior seasons, estimating its effectiveness at around 40%. “Even with that, it still prevents you from getting sick 40% of the time,” he added. While some residents, like Denver’s Briana Reilly, opt not to receive the flu vaccine, many families make it part of their routine. “I do get the flu shot, and I do make my kids get the flu shot too,” Sweer remarked.
As of now, CDPHE has confirmed one pediatric flu death this season. Dr. Post emphasizes the importance of vigilance, particularly for vulnerable populations. “There is a subgroup of folks that are immune suppressed or have bad diabetes or whatnot, that are actually very susceptible to bad things happening,” he cautioned. Despite the lower effectiveness of the vaccine, CDPHE reports that it still plays a crucial role in preventing hospital visits, reducing them by approximately 75% in children and about 33% in adults.
With three months remaining in the flu season, health officials urge the public to remain cautious and proactive in protecting themselves and their communities. The situation underscores the importance of vaccination and awareness as Colorado navigates this challenging flu season.