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7 Flu Symptoms and How – or Whether – They Differ From Signs of a Cold


Is this time of the year cold season or flu season? Truth is, it’s both. And the confusion between these two sicknesses doesn’t end there.

Flu, short for influenza, is a family of related viruses that cause a specific group of unpleasant symptoms.

Confusion enters the picture because other disease organisms – like cold viruses – can cause flu-like symptoms. So it can be hard to know for sure what illness you may be dealing with.

Let’s compare symptoms that are common between the flu and colds:

Fever– Fevers tend to come on more quickly with higher temperatures with the flu.

Chills – Chills are much more common with flu because fevers from flu tend to be higher.

Exhaustion – While a cold may make you tired, the flu will make you absolutely exhausted. If you are tired enough to want to stay in bed, it could be either one. If you feel too exhausted to blink, it very well could be the flu.

Body aches and headache– Oh, my aching… everything! Body aches are more common with the flu. This is one big clue to differentiate between a cold and the flu. Throbbing headaches are common with the flu.

Cough– A dry cough or one that produces thick yellow or green phlegm could be either flu or a cold.

Nasal and sinus congestion– More common with a cold. Usually less intense with the flu.

Vomiting and diarrhea – Not very common with the flu, but by no means do these symptoms rule out influenza infection.

The Best Way to Avoid Getting Sick

We know these two diseases are caused by microscopic invaders, so you may ask, “Why not give antibiotics to everyone with flu-like symptoms?”

Antibiotics do not kill viruses. Period. So, if you feel miserable with the “flu” and your doctor doesn’t give you antibiotics, this is why.

You then may ask, “Well then, why worry about the virus if we can’t kill it? Why not just treat the symptoms and ride it out?”

For some of these illnesses, that is the only option. However, influenza can be really nasty.

According to the Centers for Disease Control (CDC), the number of deaths from the 1918 influenza pandemic was estimated to be at least 50 million worldwide with about 675,000 occurring in the United States.

Well that was 100 years ago, and today we have… what? Antibiotics? Antibiotics don’t work on viruses, remember?

So, what can we do? Get a flu shot!

A Word About the Flu Vaccine

Vaccines help your body recognize and fight particular viruses. But getting the flu vaccine will not 100 percent guarantee that you won’t get the flu.

Why is that? First, some details about the flu virus.

There are four types of influenza. Influenza A causes roughly 75 percent of flu infections in people. Influenza B makes up the other 25 percent, but there are only two strains of influenza B.

Influenza C does infect humans, but is so mild we do not bother adding it to immunizations. Influenza D does not infect humans.

Viruses are very good at swapping DNA and creating new varieties. Influenza A has around 200 different cousins in their clan, and even those tend to subdivide slightly. That’s way too many different vaccines to even attempt. So scientists study the strains of influenza A in the population to figure out the biggest threats in the coming year. They are often very, very right.

But viruses can swap DNA fast, making new strains. Or a minor strain can bolt into the lead in the race for viral dominance. Or you can just be unlucky enough to get hit by one of those minor strains.

Even so, if you get a flu shot, there is a good chance you will get by this year without the flu. Furthermore, as one of millions who got a flu vaccine this season, you have possibly helped the entire world avoid a replay of 1918.

Steven Baldridge, RN, is a staff educator at UH Samaritan Medical Center.

Related Links

Learn more about the types of flu, flu symptoms and other flu-related information, such as when to see a doctor.