woman sick on the couch with the flu

The Flu & The Flu Vaccine: What You Should Know

March 04, 2016

The terms colds, flus and ‘flu like’ illness are used so interchangeably that it can be hard to understand the difference. But how do you know if you have just a cold or the flu? Unlike a common cold, the flu can be serious and can leave you feeling very unwell. Here's all you need to know about the flu and the flu vaccine.

The Flu & The Flu Vaccine: What You Should Know

Wondering what makes a cold different to the flu? And how to prevent or treat it? Here's everything you need to know about the flu and the flu vaccine. 

The Common Cold

The common cold and influenza are both caused by viruses. Cold viruses (e.g. RSV) are unpleasant but self- limiting conditions with symptoms rarely lasting more than a week to 10 days. Complications are uncommon in otherwise well people.

The Flu

The influenza virus or flu is most common in winter months with epidemics (outbreaks) occurring each year. The exact strain of the flu virus circulating varies from year to year (there are many different subtypes or ‘strains’ e.g. H1N1). The flu causes at best an unpleasant and debilitating short term illness and at worst it can potentially be fatal.

Flu symptoms

Real influenza once experienced is seldom forgotten. It hits like a truck! Symptoms are similar to that of a cold but will come on suddenly.

  • It can affect your nose, throat and chest (runny/stuffy nose, sore throat, cough)
  • headache
  • a very sudden onset of high fever (>38C)
  • fatigue
  • muscle pain

Symptoms will last up to 10 days to 2 weeks and typically even a fit, well adult will be required to have bed rest, may lose weight and be unable to work.

Treatment & Complications

For those who are more vulnerable; the elderly, the very young, pregnant women and those with chronic diseases or underlying medical conditions that weaken the immune system: complications of influenza can be very serious.

Because flu (and the common cold) is caused by a virus, it cannot be treated by antibiotics – however antibiotics may be needed for complications of flu such as bacterial pneumonia.

In those most at risk, respiratory complications such as sudden breathing difficulties and secondary bacterial infections like pneumonia are the most severe. There are many cases of intensive care admissions and some deaths each year related to this. The majority of those who die during flu outbreaks are elderly (80 – 90% are over 65).

Looking to get over a viral infection and build up your immune system? Here are 5 of the best natural antivirals to try.

What to do if you have the flu?

Thankfully most people who get the flu feel very unwell for 2 weeks then recover with simple measures such as fluids, bed rest and OTC pain relief like paracetamol or ibuprofen to control fever and help with discomfort. Ideally it is best to avoid a doctor’s surgery or hospital which can contribute to spreading the outbreak. Coughing, sneezing and touch can transmit the flu virus.

However for those in the ‘at risk’ groups, it may be wise to seek a medical opinion. Some are recommended to take antiviral medication at the initial onset of the illness and others may need assessment to see if there is any evidence of complications from the illness such as dehydration or pneumonia.

The Flu Vaccine

As with most things prevention is better than cure. A flu vaccine is available every year and is recommended for certain at risk groups.

Who should get the flu vaccine?

The flu vaccine is available every year from the autumn and is highly recommended for all in the ‘at risk’ groups which includes pregnant women for whom it is considered safe in all trimesters. For most of these people, the vaccine itself is free (although there may be a small cost to administering the vaccine in some cases).

As the strain of flu vaccine varies from year to year, a new vaccine is brought out each year that is felt to be the best match for the 3 or 4 most likely circulating flu viruses that season.

Can I still get the flu if I've received the vaccine?

All of us have met someone who ‘got the flu’ after their flu vaccine. While it is true that getting the vaccine is not 100% protection against the flu, it is safe to say that the flu vaccine does not give you the flu. Many people have a minor reaction of short lived fever or aches and pains for 24-48 hours after a vaccination. This is the body’s natural response to the vaccine and indicative of a healthy immune system at work.

Flu vaccines are given at the most common time of year for all colds and flu like illnesses, so it is not uncommon for people to catch one of these other viruses in the weeks surrounding your vaccine. Everyone’s underlying health is individual and may effect how well a vaccine takes.

A new vaccine is needed every year

The important thing to remember is that a new vaccine is needed each year and that all people in the ‘at risk’ groups, at least, should avail of it. For more advice on how to avoid getting sick come winter time, have a read of how to stay healthy this cold and flu season. For more useful information on the flu vaccine, see the HSE

Please note, this blog is for informational purposes only and should not replace medical advice.

It’s always best to consult your doctor before taking any new supplements, treatments or remedies if you are pregnant, breastfeeding or on medication.

Looking for a nutritional boost? Check out our blog 'The Top Five Ingredients Of Good Green Vitality' to find out why you should add it to your diet!

Checked and updated: 15 August 2021