Flu season is among us, and a new strain has emerged as a major threat.

Influenza A H3N2, or the subclade K variant, has been detected as the culprit in rising global cases, including in the U.S.

In an interview with Fox News Digital, Dr. Neil Maniar, professor of public health practice at Boston’s Northeastern University, shared details on the early severity of this emerging strain.

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“It’s becoming evident that this is a pretty severe variant of the flu,” he said. “Certainly in other parts of the world where this variant has been prevalent, it’s caused some severe illness, and we’re seeing an aggressive flu season already.”

The variant seems to differ from prior strains of the flu, with heightened versions of typical symptoms like fever, chills, headache, fatigue, cough, sore throat and runny nose.

Subclade K is the “perfect storm” for an aggressive flu season, Maniar suggested, as vaccination rates overall are down and this year’s flu vaccine does not address this specific strain.

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“The vaccine is very important to get, but because it’s not perfectly aligned with this variant, I think that’s also contributing to some degree to the severity of cases we’re seeing,” he said. “We’re going in [to this flu season] with lower vaccination rates and a variant that in itself seems to be more aggressive.”

“There’s a lot of concern that this could be a particularly difficult flu season, both in terms of the total number of cases [and] the severity of those cases.”

Because subclade K is “quite different” from prior variants, Maniar said there is less natural immunity at the community level, further increasing the risk of spread and severity.

Those who are unvaccinated are also at risk of experiencing more severe symptoms, as well as a higher risk of hospitalization, the doctor emphasized.

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In addition to getting vaccinated, the doctor recommends washing hands frequently and properly. While the flu can spread via airborne transmission, a variety of other illnesses, like norovirus, can stick to surfaces for up to two weeks, he added.

The holiday season also boosts the risk of infection, as gatherings, large events, and packed planes, trains and buses can expose people to others who are sick.

Those who are not feeling well or exhibiting symptoms should “please stay home,” Maniar advised — “especially if you think you are in that contagious period of the flu or any of these other illnesses that we’re seeing … whether it’s norovirus or COVID or RSV.”

“If you’re not feeling well, stay home. That’s a great way to recover faster and to ensure that you’re not going to get others around you sick.”

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For those who are unsure of their health status or diagnosis, Maniar recommends seeing a healthcare provider to get tested. Some providers may be able to prescribe medication to reduce the severity and duration of the illness.

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“It’s important that everyone stays vigilant and tries to take care of themselves and their families,” he added.

As snow blanketed parts of the U.S. this week, heart health experts have shared warnings of the physical strain shoveling can take — particularly for older adults.

A 2025 Mayo Clinic review found that just 10 minutes of heavy snow shoveling can push the heart to about 97% of its maximum rate. Exposure to cold air was also found to increase blood pressure and reduce coronary blood flow.

While there isn’t an official age that’s “too old” to shovel, some cardiologists recommend that individuals over 45 should exercise more caution to lower their chances of a cardiac event.

When to take caution

“While there’s no strict age cutoff, generally above the age of mid 40s and above, we tend to be a little more cautious — particularly in people who are less active [without] regular exercise,” Dr. Navjot Kaur Sobti, M.D., an interventional cardiologist at Northwell’s Northern Westchester Hospital in Mount Kisco, New York, told Fox News Digital.

“Certainly in people who are above the age of 65 — and who have risk factors for heart disease, such as high blood pressure, high cholesterol, diabetes, obesity or sedentary lifestyle — we recommend being very, very cautious about shoveling snow,” she advised. 

Dr. John Osborne, M.D., a practicing Texas cardiologist and volunteer for the American Heart Association, shared similar guidance for people older than 45, especially males over 65.

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“Unless you are in good cardiovascular shape and conditioned, it may be a good idea to ask someone for help,” he said in an interview with Fox News Digital.

The impact of snow removal is especially concerning for those with existing cardiovascular risks and a history of heart attack or stroke, according to the cardiologist. “People with these characteristics and those who have had bypass surgery or coronary angioplasty simply should not be shoveling snow in any conditions,” he said.

Osbourne said he often sees cardiac episodes in people who are typically sedentary and sit at a computer most of the day with little or no exercise. “Then once or twice a year, they go out and try to shovel the driveway after a heavy snowfall, and that unexpected exertion can unfortunately lead to tragedy.”

Hidden strain

The stress that is placed on one’s heart while shoveling snow is similar to what occurs during a cardiac stress test, Sobti pointed out, and may even exceed it.

Cold temperatures can cause blood vessels to constrict and blood pressure to spike — which, coupled with existing hypertension and the exertion of lifting snow, can significantly tax the heart, she warned.

“It’s almost like an at-risk person is putting themselves through an unsupervised maximal exertion stress test without a cardiologist actively monitoring them,” Sobti told Fox News Digital.

In addition to the exertion of shoveling, frigid temperatures can also strain the heart. Recent research has shown that cold exposure accounts for nearly twice as many cardiovascular deaths as heat exposure, including heat exhaustion.

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That study, published in the Annals of Internal Medicine last month, also found that those over age 65 had higher rates of temperature-related deaths.

“So the risk is very, very high,” Sobti cautioned. “It’s really that sudden rise in blood pressure coupled with the physical stress of snow shoveling itself.”

Safer shoveling tips

The cardiologist said it’s ideal to have someone else help with snow removal — but if you do choose to use a shovel, she recommends pacing yourself and using a “pushing or sweeping” motion instead of heavy lifting.

To protect against the cold, Sobti also recommends covering your mouth, nose and extremities, wearing a hat and gloves, and using extra caution in windy conditions.

Using an automated snow blower can still raise the heart rate — up to 120 beats per minute, compared to 170 while shoveling, the American Heart Association states on its website.

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It is also important to be aware of any symptoms of a potential cardiac issue while shoveling, Sobti emphasized.

If a person starts to experience warning signs such as chest pain, shortness of breath, a racing heart or palpitations, those should not be ignored.

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Even if the symptoms resolve after a few minutes, a person “could still be experiencing symptoms of a heart attack” and should call 911 for evaluation, Sobti said.

“It’s better really to be safe than sorry.”

More than three-quarters of the global population is falling short on omega-3 intake, a nutrient gap that may increase the risk of heart disease, cognitive decline, inflammation and vision problems.

That’s according to an analysis published in Nutrition Research Reviews, in which researchers from the University of East Anglia, the University of Southampton and Holland & Barrett analyzed omega-3 intake patterns across multiple countries and age groups.

The review found that 76% of people worldwide are not meeting the recommended levels of two omega-3 fats that are essential for heart health: eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA).

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The analysis considered recommendations from global health authorities and assessed how closely populations follow them.

Most adults should aim for at least 250 milligrams of EPA and DHA per day, though actual intake is far lower in many regions, according to the researchers.

To explore the health implications of low omega-3 intake, Fox News Digital spoke with Michelle Routhenstein, a New York–based preventive cardiology dietitian at Entirely Nourished.

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Low omega-3 levels can have a noticeable impact on heart health, cognitive function and inflammation throughout the body, the expert confirmed.

Low intake can also increase the risk of heart attacks and sudden cardiac death, she added. It’s also associated with higher triglycerides, irregular heart rhythms and plaque in the arteries.

Inadequate omega-3 levels have also been linked to changes in brain function, including faster cognitive decline, a higher risk of Alzheimer’s disease and increased rates of depression.

Routhenstein noted that low levels may also worsen inflammation in autoimmune conditions such as psoriasis, and can negatively affect eye health, since omega-3s play a key structural role in the retina.

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To improve omega-3 levels, the expert said it’s important to understand how much is needed and where to get it.

“The richest dietary sources of EPA and DHA are oily fish, such as salmon, mackerel, sardines, herring, trout and anchovies,” Routhenstein told Fox News Digital.

Many people benefit from eating oily fish more frequently, often three to four times per week, Routhenstein noted. For individuals who do not eat fish regularly, supplements can help raise EPA and DHA to healthier levels.

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For those taking omega-3 supplements, dosing should be based on lab results, medications, omega-3 levels and overall medical history, according to Routhenstein. Moderate, quality-controlled supplements are generally considered safe for most people.

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There is also some evidence supporting prescription-strength omega-3 products.

“High-dose EPA, such as 4 grams per day of icosapent ethyl, has been shown to reduce major cardiovascular events in certain high-risk populations, while similar doses of mixed EPA/DHA have not consistently shown the same benefit,” Routhenstein said.

Testing omega-3 levels can also help determine whether intake is adequate. The omega-3 index, a blood test that measures EPA and DHA in red blood cells, is considered one of the most reliable ways to assess status.

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“Levels around 8% are associated with lower cardiovascular risk, while levels below approximately 4% are considered low,” Routhenstein said.

Understanding baseline levels can help guide more personalized decisions about diet and supplementation.

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Those who are unsure about their omega-3 status or whether supplementation is appropriate should speak with a healthcare provider to determine the best approach.