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Everything to Know About the Flu This Year

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Last year, an estimated 80,000 people in the U.S. died from flu-related complications, according to data from the Centers for Disease Control and Prevention, making the last flu season the deadliest in at least four decades. With that in mind, it’d be understandable if you’re worried about this year’s flu: wondering whether it will be as severe as last season’s and what you can do to prevent the virus from affecting you. Here’s the latest news from the CDC on the 2018 - 2019 flu season, and some insight from flu experts.

First things first, do we know if this year’s flu season will be as bad as last year’s?
The CDC started monitoring the flu in October, and the season should last through the spring. Earlier this month, Kristen Nordlund, press officer for the CDC, told the Cut, “It is too early to say how severe the season will be, however, flu activity is expected to continue to increase over the coming weeks.” But even though it’s early, we have some information about what’s going on with the flu.

So, what is going on with the flu right now?
The CDC’s latest weekly flu surveillance report accounts for flu instances through January 12. The CDC estimates that, since monitoring began on October 1, over 8 million Americans have had the flu. More than 4 million people have gone to the doctor with flu symptoms so far, and between 95,000 and 114,000 people have been hospitalized. Nineteen children have died from the flu so far this season.

Are we going to get data like this each week?
Yes. The CDC has released weekly surveillance reports in previous flu seasons — but it hasn’t released weekly estimates like this in the past. “This is the first year that we’re actually reporting these numbers during the season, and going forward we’re going to be reporting them every week,” Dr. Alicia Fry of the CDC told NBC News. So, we’ll keep updating this post as new data becomes available.

Okay. But how does the flu this year compare to last year’s?
Flu expert Stephen Ferrara, associate dean of clinical affairs at Columbia University School of Nursing, told the Cut that as of earlier this month, the flu season has been following a more traditional pattern — in contrast with last year’s, which was more unpredictable. So there are already some visible differences. However, although it looks like this year’s influenza may not be severe as last year’s, Ferrara stressed that the flu is always dangerous in any circumstances.

Wait, please explain these “differences.”
Basically, each year, different mutations of the influenza virus circulate; certain strains tend to be more dominant than others, depending on the season. The prominent strain last year was Influenza A (H3N2). The virus circulated earlier in the season than usual and was more virulent than had been seen in prior years, which contributed to it being a particularly difficult strain, according to the expert. On top of that, after the H3N2 virus reached its peak by early February, a strong surge of Influenza B cases popped up and spread through the spring. That’s a fairly regular occurrence after a H3N2 spread, but different than what you might see after other strains reach their peaks.

So this year, Ferrara notes the flu seems to be following a more “predictable” pattern: There’s been the traditional spike in cases in the weeks of December, and a more common strain — Influenza A (H1N1) — has so far been dominant. There are still cases of H3N2, but fewer than last year. But keep in mind that both of these strains are still mutations of the same Influenza A virus; it’s just that we’re more likely to have built up some immunity to H1N1 (which emerged in 2009), whereas H3N2 is a newer mutation.

Excuse me … are you talking about the swine flu?
Yes, H1N1 is also known as the “swine flu,” but please don’t be overly alarmed. The strain is dangerous — say it with me: All strains of the flu are dangerous — but this outbreak should not be as bad as the 2009 pandemic, which one study found may have led to approximately 280,000 deaths worldwide. You see, during the pandemic, a special vaccine for the H1N1 strain was created — and the strain also became a more regular fixture of flu seasons moving forward. So, our bodies (hopefully) now have some immunity to it. Ferrera told the Cut that now, a typical flu vaccine includes two variants of Influenza A (both H1N1 and H3N2) and at least one strain of Influenza B, so if you get the flu shot, you will hopefully be covered.

So, you’re saying I should get a flu shot?
Please forgive this emphasis, but yes, yes, yes, a million times yes! According the CDC’s Nordlund, the flu vaccine is the safest bet to reduce the risk of the flu and its serious complications. I got my flu shot back in October, but Ferrara says it’s not too late for others to do the same. “We continue advocating for people to get them, and especially now, if people were to get it, it will cover them in the typical peak season,” he said. “It does take your body about 10 to 14 days to develop immunity from the vaccine, but certainly there is still time. We haven’t seen the worst of this season yet.”

Other than that, how can I prevent the flu?
It’s still the same common-sense practices we were taught as children: Wash your hands and/or use alcohol-based sanitizer, stay home when you’re sick, cover your mouth if you cough, dispose of dirty tissues in a way that won’t make other people exposed to them, and avoid being around sick people if you can.

What flu symptoms should I keep an eye out for in the 2018–2019 season, and what should I do if I think I’m coming down with the flu?
Ferrara told the Cut that there are some very classic flu symptoms to keep an eye out for: a nonproductive cough, fever, and body/muscle aches in adults; and children may also experience nausea and vomiting on top of those other symptoms. So, if you’re experiencing any of that, it’s important to head to the doctor immediately. There’s an antiviral drug that can be taken within the first 48 hours of the flu that might help you (if your doctor decides you’re a good candidate for the medication). Nordlund noted that people at risk of serious complications from the flu and children should especially seek immediate medical assistance.

And how long does the flu last?
Generally speaking, when it comes to the flu, acute illness can last four or five days, though your cough can linger for weeks. But it can also take a while to snap back from the flu, since “it really is debilitating, especially if you have a full-blown case,” Dr. Arnold Monto, a professor of epidemiology at the University of Michigan School of Public Health, told the Cut last year. People are usually only contagious for five days at the most if they have the flu (and maybe a bit longer if they’re younger), and it’s recommended that people stay home from work three to five days if they’re sick.

This post has been updated.

Everything to Know About the Flu This Year