You wake up and you just know it.

You’re congested. Your head is throbbing. You’re running a fever. You feel like you’ve been hit by a truck.

It’s flu season and you’re one of its casualties.

“We probably see a few with influenza or an influenza-like illness every day during the flu season,” said Dr. Marsha Cushman, medical director of the emergency center at ProMedica Fostoria Community Hospital.

The Centers for Disease Control and Prevention estimates that between 9 million and 45 million cases of the flu have taken place in the United States since 2010. It should be taken seriously, as it has been responsible for an estimated 12,000 to 61,000 deaths.

And the United States is in that time period when the flu hits hard and often.

“As the temperature drops, that’s kind of when it starts and it doesn’t really stop until the temperature warms up again, more than likely,” Cushman said. “For us in Ohio, it’s probably October, November all the way until, sometimes, March. As soon as it gets colder and everybody comes inside is pretty much when it starts.”

So, there you have it: Contrary to popular belief, the weather itself is not responsible for people getting sick.

“People always say that and it’s so wrong,” Cushman said. “It’s just because it’s that time of year and it’s common for people to be in closer contact with each other and it’s easier to spread the virus. Everybody’s inside and not doing their normal stuff, and then the virus likes the type of humidity (indoors) in this type of weather, so it’s easy to spread that way.

“It’s easy to spread. That’s the problem. You can spread it in air droplets. You can spread it by direct contact — by touching, by kissing. It’s very easy to spread, which is why it’s such a crazy illness and goes across the entire United States every year. It’s a very virulent virus. There are a ton of different strains of it, not one unique virus. A ton of viruses causes influenza-types of illnesses, and they’re very easy to spread, they’re very common and there’s no cure.

“So, if people don’t vaccinate themselves, it’s never going to stop. And even with the vaccine, it’s never perfect. It’s just a very common, very easy-to-get virus. That’s why it keeps doing its thing.”

Cushman said she considers the flu vaccine to be “very effective” in helping people avoid the bug, and it’s still a good idea to get the shot if someone hasn’t already for this season.

“Each flu vaccine is designed every year for what the CDC thinks is out there,” she said. “It’s a very educated guess at which particular virus is going to be there, so you can still get a virus that’s different from the ones you’re vaccinated for. That’s why people get frustrated with it — because it’s not perfect; it’s not going to catch everything. But they also suggest that if you get (the shot), you’re going to feel less sick than if you wouldn’t have got it. The illness should be less of a problem for you because you’ve already built up the antibodies, so it has some secondary benefits as well, plus it does prevent the spread of the disease, which is what people forget.”

Cushman offered other methods of limiting the spread of the flu.

“Be diligent about hand washing, be diligent about staying away from others who are ill, stay home if you get sick so you don’t spread it,” she said. “It’s mostly hand washing, making sure people cover their mouths when they cough, stuff like that.”

There’s no cure for the flu, so, basically, you’re simply going to have to deal with it by treating the symptoms properly, getting plenty of rest, taking in plenty of fluids and eating what you can, according to Cushman.

She said that while prescription antivirals may be good for flu victims with other conditions such as asthma or diabetes, they will accelerate the process of the virus running its course by only a day and may have nasty side effects.

She said those who get flu symptoms should stay alert to the possibility of it being something more serious that requires the attention of a doctor.

“If you’re doing OK and you’re drinking fluids and you feel like you have the flu, that’s OK, you can stay home,” she said. “If you’re feeling like you can’t tolerate fluids or you’re feeling really short of breath or things like that, you should see someone, for sure.”