As the world braces for another challenging influenza season, public health officials from Latvia to the United States are sounding the alarm over a rapid uptick in flu cases, the emergence of new viral variants, and growing concerns about vaccine hesitancy. The 2025-2026 flu season, experts warn, is shaping up to be both unpredictable and potentially severe, with children and vulnerable populations at particular risk.
In Latvia, the latest surveillance data paints a stark picture. According to the country’s Centers for Disease Prevention and Control (CDC), the proportion of positive influenza samples reached 9.1% in the week before December 4, 2025—just a hair shy of the 10% epidemic threshold. That’s a significant jump from the previous week’s 5.9%, and it comes as 22% of patients visiting family doctors reported respiratory infection complaints, five percentage points higher than the week prior. The average incidence rate has soared to 125.3 cases per 100,000 residents, nearly doubling in just seven days.
The brunt of this surge is being felt by children aged 5-14, who now account for the highest incidence of influenza in the country. But the virus isn’t sparing older Latvians either; increases have been recorded across all age groups. Outbreaks have been detected in eight out of ten monitored regions, with the city of Jelgava experiencing the most intense activity, and cases cropping up in Riga, Jūrmala, Rēzekne, Daugavpils, Gulbene, Jēkabpils, and Valmiera municipalities.
Laboratory data backs up these trends. Of 317 clinical samples tested last week, 9.1% were positive for influenza. Since the start of the season, 68 cases of influenza type A have been confirmed, with subtype A/H3 accounting for 72.5% and subtype AH1pdm for 27.5% of the 51 subtyped cases. Notably, no influenza type B virus has been detected so far this year.
Latvia’s CDC has also noted a parallel, though less dramatic, trend in Covid-19. After a spike in late summer and early autumn, the infection rate has stabilized, but the proportion of positive tests has hovered around 5% for the last three weeks. Last week, 544 Covid-19 tests were conducted, 26 of which (4.8%) came back positive. Hospitals admitted 31 patients for Covid-19, with 23 having it as their primary diagnosis, and one Covid-related death was recorded.
What’s especially concerning to public health officials is that this year’s flu season started earlier than usual—a pattern seen not only in Latvia but across Europe, according to the European Centre for Disease Prevention and Control. The dominant strain, influenza A(H3N2), is notorious for its rapid spread and its ability to cause severe illness, particularly in older adults, people with chronic diseases, and pregnant women.
With the virus gaining momentum, the CDC is urging residents—especially those in high-risk groups—to get vaccinated as soon as possible. As of December 3, 2025, 116,077 Latvians have taken advantage of the state-funded flu vaccination program, which prioritizes the elderly, people with chronic conditions, pregnant women, and healthcare workers. The goal, officials stress, is to reduce the risk of severe illness and death. Vaccination against both seasonal influenza and Covid-19 is strongly recommended for those most at risk of complications.
Information about which healthcare institutions offer state-funded flu vaccines is available on the CDC’s website and is updated regularly based on vaccine availability. The message is clear: “The main goal of vaccination is to reduce the risk of severe illness and death,” the CDC notes. “Vaccination is especially recommended for people who often experience severe forms of acute respiratory infections and those at high risk of complications when ill.”
Across the Atlantic, the United States is facing its own set of flu-related challenges. While the 2025-2026 season began with relatively low activity, health officials expect a significant rise in school absences and sick children as a new variant, H3N2 subclade K, gains traction. This variant has already led to spikes in hospitalizations in Canada and the U.K., raising concerns that the U.S. could soon see a similar pattern.
There’s another wrinkle: the flu vaccine for this season may be less effective against the H3N2 subclade K variant. Nevertheless, experts insist that vaccination remains the most effective tool for preventing severe illness and curbing hospitalizations. “Even an imperfect influenza vaccine—let’s say it shaves 30 percent off of your influenza risk—is still probably shaving even more off your risk of getting severe influenza,” said Ryan Maves, professor of infectious disease at Wake Forest University, to Nexstar Media. “Your likelihood of going to the ICU is much lower. Your likelihood of getting hospitalized is much lower, your likelihood of death is much lower.”
Despite these reassurances, vaccination rates in U.S. schools are slipping. The Centers for Disease Control and Prevention (CDC) reports that in the 2024-2025 school year, rates for required vaccines such as DTaP (diphtheria, tetanus, and acellular pertussis) and MMR (measles, mumps, and rubella) dropped to around 92% among kindergartners, down from about 95% before the pandemic. Exemptions have also crept up, with 17 states now reporting exemption rates above 5%—well below the 95% threshold needed for herd immunity. No state currently requires flu vaccination for school attendance, and last year, less than half of students got the flu shot.
Health experts stress the communal responsibility of vaccination. “Vaccines are not just for each of us as individuals. They’re for everyone,” said Ron Marino, a member of the Council on School Health Executive Committee at the American Academy of Pediatrics, in an interview with Nexstar Media. “If there are children in your child’s school who have immune suppression, who have leukemia, have other diseases, and if they get the flu or viral illness, they might get significantly more ill than a child who has a normal immune system or is not on drugs that may suppress their immune system.”
Schools, meanwhile, are struggling to manage outbreaks amid chronic absenteeism and staffing shortages—a lingering effect of the pandemic. “I think rather than look for a specific percent of students, you really have to look at symptoms that they present,” said Lynn Nelson, president of the National Association of School Nurses. Anecdotal reports from parents and clusters of symptoms like sudden high fever are now key indicators for detecting outbreaks in the absence of reliable absenteeism data.
Last flu season in the U.S. was one of the worst in recent memory, with over 280 children dying—many of whom were unvaccinated. “That is a heartbreaking reminder of how serious the flu can be—nearly one-third of children hospitalized with the flu had no underlying health conditions but were largely unvaccinated,” said Sarah Nosal, president of the American Academy of Family Physicians.
As the 2025-2026 flu season gathers steam, the message from health officials on both sides of the Atlantic is unmistakable: vaccination, vigilance, and community cooperation are more crucial than ever. The stakes are high, and the path forward will require both individual action and collective resolve.