Flu Surge in Massachusetts: A Perfect Storm

Local healthcare professionals are warning of a concerning situation: a rapidly spreading strain of influenza A, coupled with declining vaccination rates and increased holiday travel, might extend the flu season well into spring.

Dr. Vandana Madhavan, who directs infectious disease at Mass General Brigham for Children, stated, “This is one of those seasons where everything is lining up in the wrong direction. It’s difficult to predict when we will hit our peak, and some years we even witness a second peak.”

By the end of December, healthcare visits due to flu-like symptoms surged to 11.8 percent, a significant rise from 7.6 percent the previous week, according to the Massachusetts Department of Public Health. Emergency room visits leading to hospitalizations for flu jumped to 9 percent—almost double from the week before and tripling the rate from the same period last year.

Last week alone, nearly 9,000 emergency department visits occurred statewide, with around a quarter of those linked to acute respiratory illnesses, including flu, COVID-19, and RSV.

In Massachusetts, last year’s flu hospitalizations peaked in early February, with approximately 10.5 percent of admissions attributed to the influenza virus. This year’s trends suggest that the state might reach or even surpass that level, Dr. Larry Madoff from the Massachusetts Department of Public Health noted.

“The flu season is likely to drag on well into the spring,” Madoff remarked. “Typically, we see a peak in late January or February.”

In response to the high rates of hospital infections, Brown University Health will mandate surgical masks or N95s for patients, visitors, and staff at all its Massachusetts and Rhode Island locations starting Tuesday.

On a national scale, the situation is similar, with the Centers for Disease Control and Prevention reporting “very high” flu activity in over half of U.S. states as of December 27. They estimate at least 11 million illnesses, 120,000 hospitalizations, and 5,000 deaths, including at least nine children.

This season, Massachusetts reported 32 influenza-related deaths, consisting of 29 adults and three children, one of whom passed away during Christmas week. In contrast, the previous year recorded 470 influenza-related deaths. The state is also looking into two potential COVID-19-related deaths and one RSV-associated death in individuals under 18.

Influenza is a contagious viral illness affecting the respiratory system, manifesting symptoms such as high fever, cough, sore throat, body aches, and extreme fatigue, sometimes along with nausea, vomiting, or diarrhea. Clinicians are now observing fevers as high as 104 or 105 degrees in some cases.

This year’s outbreak seems particularly intense, driven by a prevalent strain of influenza A H3N2, specifically a genetic variant referred to as subclade K.

Among influenza A H3N2 viruses analyzed by the CDC, around 90 percent belong to this subclade. Although experts are still determining whether it leads to more severe illness, early evidence indicates it spreads more rapidly and may evade existing community immunity more effectively.

Internationally, subclade K has raised significant concerns. UK health leaders alerted in November about a “once-in-a-decade” flu surge as infections spiked among younger populations. This strain has also been identified in Canada and Japan, where authorities announced a flu epidemic as early as October.

Dr. Zachary Binder, an associate professor in pediatrics at UMass Chan Medical School, shared, “It really did feel like a switch flipped. We transitioned from almost no flu cases to over half the patients in the emergency department testing positive for the virus.”

Binder noted that over 50 percent of his recent patients had influenza A, and many children experienced febrile seizures due to dangerously high fevers.

“We are witnessing a significant surge in flu cases in the past few weeks,” he added. “When severe cases arise, including fatalities, they are most frequent in children with underlying health issues like asthma or other respiratory and cardiac conditions.”

Vaccination rates are another major concern. Only about 34 percent of Massachusetts residents have received a flu shot this season, a decline from the previous year’s 40 percent.

Adding to the complications, the newly mutated strain—which surged earlier in the UK—doesn’t seem to be a perfect match for this year’s vaccine. Scientists must predict which flu strains will circulate several months in advance, and this year’s predictions somewhat missed the target.

Madoff from the state health department emphasized that even though the circulating strain is not a perfect match, “a vaccine is far better than no vaccine.”

He expressed regret over the drop in vaccination rates in the state and criticized recent federal decisions that seemed to undermine recommended childhood vaccinations.

“I think it’s the wrong move at the wrong time,” Madoff stated. “It contradicts what healthcare professionals recommend. We shouldn’t weaken these essential protections for our kids.”

The decline in flu vaccination rates stems from various complex factors. Some experts believe pandemic fatigue plays a role—like fewer routine care visits and lingering skepticism about vaccines after COVID-19. Others think people might underestimate the seriousness of influenza compared to other respiratory viruses.

Despite this, physicians in Massachusetts stress that getting vaccinated dramatically reduces the risk of severe illness, hospitalization, and death.

“It takes a couple of weeks to gain full protection from vaccination,” Madhavan advised. “Now is the critical time to get vaccinated if you haven’t yet.”

Pediatric specialists are witnessing a concerning increase in severe complications in children this year. Madhavan mentioned treating patients with acute necrotizing encephalopathy, a rare and serious consequence of influenza that can lead to drastic changes in mental status, communication challenges, and in severe cases, difficulty breathing.

Though severe flu cases are more common in children with underlying health conditions, doctors caution that even otherwise healthy children can fall critically ill, urging parents to observe for signs like dehydration, breathing difficulties, persistent high fever, or extreme lethargy.

For those managing care at home, Madhavan recommends ensuring proper hydration—popsicles and electrolyte solutions like Pedialyte are helpful—as well as controlling fever with ibuprofen or acetaminophen. For children over one, honey can also provide relief from coughs.

Currently, COVID-19 activity in Massachusetts remains relatively low when compared to influenza, though health officials warn that seasonal waves can overlap.

For now, doctors and public health officials are encouraging everyone to get vaccinated, stay home when feeling unwell, wash hands often, and seek medical help early if symptoms worsen.

Madoff urges individuals to seek care promptly when symptoms first appear. “There are treatments available, and initiating them sooner is more beneficial,” he stated. “For vulnerable populations like young children and older adults, treatments such as Tamiflu can be lifesaving.”