What are the symptoms of flu, how long do they last and when should I see a doctor?

30 March 2017  |  Editor

What is Flu

Flu can be associated with a variety of symptoms, some of which are common with other viral infections such as the common cold. However, flu symptoms are inclined to be more severe and prolonged, and there is a risk of developing complications such as bronchitis or pneumonia. Here we describe the different symptoms and complications of the flu, and when you need to seek help from your doctor.

What are the symptoms of the flu?

Flu is caused by the influenza viruses. Although there are a few types of flu viruses, the same symptoms generally appear. These include:

  • Fever
  • Excessive sweating and night sweats
  • Aching joints
  • Sore throat
  • Coughs
  • Nasal congestion
  • Diarrhoea
  • Vomiting
  • Fatigue

These are very much the same symptoms as may be experienced with colds. However, in general, flu gives rise to more severe symptoms and a severe cold may sometimes be treated as flu.

Occasionally, severe flu symptoms may be experienced with the development of serious medical conditions or complications.

How long will flu symptoms last?

The length of flu infection will depend on the individual. Generally speaking, symptoms persist for about a week, although this can be much longer with a severe infection or in someone with a weakened immune system.

The first indication that you have the flu is often a sudden high temperature and fever.  You may feel that you have achy muscles. Your temperature will probably go down within 48 hours.

After this, your symptoms may become more like a cold. You might suffer from a sore throat, and a dry cough. This is because your immune system is now releasing chemicals to attack the flu virus, but these chemicals irritate your respiratory system causing these symptoms. You may also start to have a runny nose. This reaction removes any cells from your body which your immune system has already killed.

You may begin to feel congested with a blocked nose after 3 or 4 days. This happens when the mucous discharge becomes thicker. This can cause a chesty cough as your body tries to get rid of the excess mucus. You may also experience a headache.

Eventually, by the end of the week, your symptoms should begin to subside and you will begin to feel like your normal self again. However, it can take a couple of weeks before you feel that you have fully recovered.

How do I know whether it’s a cold or the flu?

It can sometimes be difficult to tell whether you have a bad cold or the flu.

To say that flu is caused by the influenza virus, and that a cold is caused by one of about 200 different viruses, is really no help at all. However, a look at the symptoms and how they arrive might make it easier to establish whether you are suffering from the cold or flu.

Cold symptoms generally appear gradually. You might have a sore throat for a couple of days before any other symptoms develop. With the flu, however, all the symptoms will hit you like a brick wall from day one. You are more likely to suffer a fever with the flu, and diarrhoea and vomiting are not uncommon.

Generally, it will not take long after your cold symptoms have gone to be up and running as usual. However, with the flu, you may still feel drained and fatigued for a week or more.

Complications of the flu

If you are normally healthy, then the flu may make you feel worn out while it runs its course, but it should not present any medical complications.

However, sometimes a complication of flu will develop, particularly if you have a weakened immune system. These include:

  • Bronchitis – this is an inflammation of the tubes which carry air to and from your lungs. It makes it difficult to breathe, and can often result in a chesty, mucous cough. This can develop into pneumonia
  • Pneumonia – sometimes a viral or bacterial chest infection can lead to pneumonia. This is the most common complication of the flu. It occurs when lung tissue becomes inflamed, making it difficult to breathe and is likely to need treatment in hospital
  • Ear infections – the most common type of ear infection is when fluid and pus build up in the middle ear. This is most common in children after a bout of cold or flu. It may clear up by itself after a few days, or need antibiotics to clear the infection.

When to see the doctor

Weak immune function makes it more difficult for the body to withstand infection, so an early sign of a weak immune system is a tendency for the body to pick up infections such as colds and flu more easily.

This happens because a poorly functioning immune system can’t spot the nasty invaders efficiently. In addition, the immune system may also take longer to overcome bugs.

It is important to remember that people with weak immune systems such as children, the elderly, and those with underlying medical problems may suffer more severe symptoms with the flu, and are more likely to need medical attention.

You should seek medical attention if you experience any of the following symptoms:

  • Severe headaches or chest pain
  • Dizziness
  • Persistent vomiting, coughing, sore throat or fever
  • Shortness of breath
  • Confusion

How Echinacea helps

Echinacea is a traditional herb known to aid the body in its fight against the symptoms of cold and flu. Supplements like Echinaforce help increase the body’s resistance to infection by strengthening the immune system, allowing the body to fight the misery of colds and flu.

Echinacea works by supporting the immune system and therefore helps the body fight the symptoms of flu. This is a licensed herbal remedy and is recognised in the European Medicine Agency as such. Beware, not all echinacea products are licensed - in fact very few are. This is important and these A Vogel range of echinacea products are regarded as the best and most effective. It also as anti-bacterial and anti-rirul activity and can kill pathogens before they infect body cells. Research shows that Echinacea boosts the immune system for those who need it but has no adverse effects for those who don't.

in 2012 the largest trial ever carried out on Echinacea showed:

  • Echinacea reduces the development of recurrent colds by 59%
  • Echinacea also reduces the symptoms of cold episodes, reducing the need for painkilling medication by 52%
  • Those most at risk – those prone to more than 2 colds per year; those with high stress levels; smokers; and poor sleepers – benefitted most from Echinacea
  • The safety profile of Echinacea when taken daily over a 4-month period was extremely good.

Many people find that taking Echinacea BEFORE any symptoms occur is the best way to build up resistance for any unpleasant bouts of flu have a chance to get hold. See some products here.