10 Facts About the Flu

From Hippocrates’s description of the flu in ancient Greece to the most recent flu pandemic in 2009, here are the essential facts about the dreaded influenza.
Peter Dazeley/The Image Bank via Getty Images

The seasonal flu is a fact of life, but you get your annual flu shot, your likelihood of suffering the flu’s unpleasant symptoms decreases. Here’s what else you should know about the ever-circulating virus.

1. The flu vaccine can’t give you the flu.

The vaccines contain a dead piece of the flu virus, and a dead virus can’t infect you. There is a nasal vaccine that contains a live virus, but that particular vaccine is designed to seek and destroy the part of the virus that actually makes you sick.

2. You can treat the flu.

Up to 48 hours after the onset of symptoms, a doctor can prescribe antiviral medicine that will help. It’s not going to get rid of the virus entirely, but it will lessen the time that you’re curled up on the couch, watching game shows and cursing life.

3. The 1918-1920 flu outbreak is the best-known influenza pandemic.

Walter Reed Hospital Flu Ward
The flu ward at Walter Reed Hospital in Bethesda, Maryland, circa World War I. / Heritage Images/GettyImages

The so-called Spanish Flu killed between 40 million and 100 million people worldwide at the tail-end of World War I. It was so severe that it registered a Level 5 (the maximum) on the Pandemic Severity Scale. The mortality rate was, by some estimates, as high as 20 percent. People that got it and survived include Franklin Delano Roosevelt, Walt Disney, Mary Pickford, General John J. Pershing, and Woodrow Wilson.

5. The flu can still be deadly.

In the U.S. alone, the flu season results in 36,000-ish deaths and 200,000 hospitalizations. As if those facts werent painful enough, the seasonal flu costs Americans a collective $10 billion annually.

6. British students come down with the “freshers flu.”

While we in the U.S. have “freshman 15,” the Brits have “freshers flu.” Up to 90 percent of people during their first few weeks at college end up getting sick, and whether it’s actually the flu or not (it’s often just a cold), the nickname has a nice ring to it.

7. People who say they have the “stomach flu” probably don't.

“Stomach flu” is a nickname that came about because it makes you feel crappy in similar ways to the real flu. But if you have only a stomach ache without additional body aches or fever, you probably just have a gastrointestinal virus of some sort.

8. You don't need to “starve a fever.”

Woman Wearing a Flu Mask
A woman wears a “flu mask” in the early 20th century. / Hulton Deutsch/GettyImages

There isn’t much truth in the old saying, “feed a cold, starve a fever.” Fever is one of the main symptoms of the flu, and if you have one, you should increase your fluid intake. But there’s no need to decrease the amount of food you eat. In fact, nibbling on healthy meals will help your body recover from the virus.

9. The flu has been around for a long time.

The Greek physician Hippocrates wrote of an illness with a description closely matching today’s modern flu symptoms.

10. The most recent flu pandemic was in 2009.

The (H1N1)pdm09 flu virus emerged in April 2009, and because it was so different than earlier mutations of the H1N1 virus, few people under the age of 60 had immunity to it. The CDC estimates that between April 2009 and April 2010, there were about 61 million cases of (H1N1)pdm09 flu, about 274,000 hospitalizations, and more than 12,000 deaths in the U.S. alone.

A version of this story was published in 2008; it has been updated for 2024.