Often when people say they have flu, they actually have a heavy cold — which can still make you feel pretty rubbish!
The two are caused by different viruses (plus there are many strains of flu virus, and no, flu isn’t just a ‘cold that got worse’).
In general, flu is more rare and serious; it tends to come on more suddenly, severely and lasts longer, and will typically leave you bed-bound with extreme exhaustion for a week.
There’s a saying about having the flu — that even if somebody put €100 at the end of your bed, you’d be too unwell to even think about reaching for it.
So, if you’re still able to get up and get on with your day — even if you don’t feel great doing it — chances are you’ve got a cold, not the flu.
“A lot of people think they’ve got flu when actually they have a heavy cold. Colds and flu are both caused by viruses, but with flu, your lungs are affected to a greater extent.
"A cold tends to cause more nasal congestion and is over in a few days, whereas with flu, it can take you weeks to recover,” notes pharmacist Nitin Makadia.
Those suffering with flu will also experience symptoms like sudden fever and sweating, feeling shivery, more severe muscle aches and pains, and a dry, chesty cough. A loss of appetite is also associated with flu.
With colds, common symptoms include a cough, blocked or runny nose, sneezing and a sore throat. Headaches can also occur for both colds and flu, and some people may feel achy with a cold too.
We might know the colder months as ‘cold and flu season’, but they can occur all year round. It is true that we see a spike in cases over autumn and winter months, though — but that’s not simply because it’s colder.
“It is not the drop in temperature that causes common colds and an increase of flu during winter,” says Boots flu pharmacist Deepa Songara.
“We spend less time outside and much longer closer together at home or in indoor places,” she adds. “This ‘togetherness’ makes it easier to pass germs from one person to another.” We also tend to close windows and crank up the central heating, creating stuffy, germ-filled environments.
While colds can leave you drained and feeling unwell, they’re rarely medically serious. Flu, however, can be very serious, especially for those who are already vulnerable, and may lead to further complications like pneumonia.
This is why flu jabs are recommended for anyone over the age of 65, pregnant women, and children and adults with long-term medical conditions such as diabetes, Parkinson’s and auto-immune disorders.
There is a wealth of over-the-counter remedies to soothe cold symptoms. Generally, you shouldn’t need to see your GP if you have cold or flu symptoms (unless symptoms are particularly severe, last far longer than usual or you have any underlying health problems), but you could speak to a pharmacist for advice on treatments, and if you’re unsure about symptoms or whether you should see your GP.
“Fluids, rest and pain relief are a must when suffering flu symptoms. This is because your body dehydrates during a fever and can cause severe body pains as a result, because the immune system is trying to attack the virus,” says pharmacist Angela Chalmers.