It’s not just your imagination. Respiratory viruses are hitting hard, and several overlapping factors explain why so many people seem to be sick at once. A combination of shifting virus seasons, lingering immune gaps from the pandemic years, and the way multiple viruses now stack on top of each other has created stretches of illness that feel relentless.
What’s Actually Circulating Right Now
Three major respiratory viruses drive most of the illness people notice around them: influenza, COVID-19, and RSV. Each follows its own seasonal pattern, but their peaks increasingly overlap, creating waves where it feels like nobody can stay healthy.
Influenza has been especially aggressive. During the 2024-2025 season, the percentage of positive flu tests from clinical labs peaked at 31.6% in early February 2025. That means roughly one in three people tested for flu during that peak week actually had it. Children have been hit the hardest: pediatric flu hospitalization rates reached their highest weekly peak since the 2010-2011 season, and cumulative hospitalization rates for kids were the second highest in that same 15-year span.
COVID-19 now follows a pattern with two peaks per year rather than one. The summer wave peaked at 17.9% positivity in August 2024, dipped through the fall, then climbed again to a smaller winter peak of 6.7% in early January 2025. That double-peak pattern means there’s no single “COVID season” anymore. You’re encountering it in summer and again in winter.
RSV rounds out the trio. It peaked in late December 2024, with 11% of tests coming back positive. RSV’s active season ran from early November through late March, overlapping almost perfectly with flu season. When two or three of these viruses circulate simultaneously, the sheer volume of sick people around you multiplies.
The Immune Gap From the Pandemic
During lockdowns and masking periods, people were exposed to far fewer everyday germs. That was the point, and it worked. But it also meant that immune systems, particularly in young children, missed the routine exposures that normally build and refresh defenses against common viruses.
This concept, sometimes called “immunity debt,” doesn’t mean lockdowns damaged anyone’s immune system. The immune system itself works fine. The problem is more straightforward: when you haven’t encountered a specific virus in a while, your body’s targeted defenses against it fade. This happens at the individual level, where a child might face RSV for the first time at age three instead of as an infant, and at the population level, where enough people lose their partial immunity that a virus can spread more freely.
The effect cascades through families. Parents who went a year or two without catching certain viruses became more susceptible, caught them, and passed them to their young children. Some mothers may have passed lower levels of protective antibodies to newborns during pregnancy because their own recent exposure to viruses like RSV had dropped. The result was a larger pool of vulnerable people at every age, not just kids, which allowed viruses to circulate faster and reach more households.
How Viruses Take Turns (and Sometimes Don’t)
Your body has a first-line defense system that kicks in quickly when any virus enters your airways. When one virus infects your respiratory cells, those cells release signaling proteins that put neighboring cells on high alert, making it harder for a second, different virus to gain a foothold. This process, called viral interference, is one reason why you don’t usually catch the flu and a cold at the exact same time.
Before the pandemic, this biological competition meant respiratory viruses tended to take turns. A rhinovirus wave might suppress an early flu outbreak, buying people a few extra weeks of health. But the pandemic disrupted these patterns. Viruses that were suppressed for a year or more came roaring back on shifted timelines, and the usual sequence broke down. RSV, flu, and COVID now overlap more than they historically did, which means the intervals where you’d normally recover between infections have shortened.
In rare cases, viruses can actually help each other. Certain infections cause neighboring cells to fuse together, creating larger structures that a second virus can exploit for faster replication. These positive interactions are less common than the competitive ones, but they add another layer of unpredictability to how respiratory seasons unfold.
Kids Are Getting Hit Harder Than Usual
Children under 18 have experienced some of the highest flu hospitalization rates recorded in the past 15 years. The cumulative pediatric hospitalization rate for the current season is the second highest since tracking began in 2010-2011, across all pediatric age groups.
Several forces converge on kids. Many toddlers and preschoolers are encountering common respiratory viruses for effectively the first time, without the gradual exposure that would have built partial immunity in a normal year. Younger siblings are catching viruses from older kids who bring them home from school. And because more adults in the community are also susceptible (thanks to that same gap in recent exposure), viruses move through households faster, giving children’s developing immune systems less time to recover between infections.
COVID Changed Its Seasonal Playbook
One reason illness feels constant rather than confined to “cold and flu season” is that COVID-19 doesn’t follow the old rules. Unlike flu and RSV, which reliably peak once per winter, SARS-CoV-2 produces two distinct waves each year: one in summer and another in winter. During the 2024-2025 surveillance period, the summer peak was actually much larger than the winter one (17.9% versus 6.7% test positivity).
This means the months that used to feel relatively safe from respiratory illness, like July and August, now carry their own wave of infections. If you or people around you got sick in the summer and then got sick again in December, that’s not bad luck. It’s the new seasonal rhythm of a virus that’s still finding its equilibrium.
Vaccines Still Help, but the Picture Is Complicated
Early data from England’s 2025-2026 flu season showed flu vaccination reduced hospitalization risk by 70-75% in children and 30-40% in adults. Those numbers are within the normal expected range for flu shots, which means the vaccine matched the circulating strains reasonably well. The lower effectiveness in adults reflects a long-known pattern: adult immune systems respond less robustly to flu vaccines than children’s do, partly because of accumulated exposure history that shapes which antibodies the body prioritizes.
Still, vaccination rates for both flu and COVID boosters have declined since the early pandemic years. Fewer vaccinated people in the community means less of a buffer against transmission, which contributes to the feeling that “everyone” is sick. Even a moderately effective vaccine, when widely used, can blunt a peak enough that hospitals stay manageable and fewer people in your office or school are out sick in the same week.
Why It Feels Worse Than It Used To
Part of what you’re experiencing is genuinely new: shifted viral seasons, a larger susceptible population, and a novel virus that peaks twice a year. But part of it is also perceptual. Before 2020, most people didn’t track respiratory virus seasons at all. A bad flu year came and went without much public attention unless you personally ended up in bed for a week. Now, after years of heightened awareness, you notice every cough in the room, every sick day at work, every round of illness your kids bring home.
Both things are true at once. Respiratory illness really is elevated compared to pre-pandemic baselines, especially in children. And you’re also more tuned in to it than you were five years ago. The combination makes the current moment feel like an unending sickness season, even as the underlying trends are gradually stabilizing as population immunity rebuilds through a messy, uncomfortable process of catching up on missed exposures.