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Influenza and the common cold

We have all heard of influenza and know it can make you feel very ill, but did you know there are only 3 types of the influenza virus (known as A, B and C) but many strains. However, the common cold can be caused by nearly 200 different viruses.

What is influenza?

Influenza commonly known as ‘flu’ is caused by a virus. The virus enters the body through the eyes, nose or mouth and travels down into the lungs. Once in the airways, the virus multiplies over and over again. As it does so it causes the first symptoms of flu – a runny nose, sore throat and a cough. The reason why you feel so bad with flu is that the body’s defence system tries to overcome the virus and releases substances to fight it. It is this reaction that causes problems elsewhere in the body, such as aching muscles, headache, fever and weakness.

What is a cold?

A cold is also caused by a virus and is probably one of the most common illnesses known. The common cold is usually mild and will only last a week or less. Colds are far more common amongst children and they can get up to 10 colds in 1 year.

What causes the flu and a cold?

Viruses cause both colds and flu and despite years of research there is still no medicine that will cure either. What you can do is relieve the symptoms with simple treatments and medicines. Controlling the symptoms will make you feel better while your body gets rid of the virus. There are three types of virus that cause the flu, known simply as type A, B and C. Type A is the most common and is the one usually associated with serious epidemics.

How are flu and colds spread?

Different viruses cause the common cold and flu, but both are spread through the air, in tiny droplets produced when an infected person coughs, sneezes or breathes. When you sneeze your body is getting rid of infected cells and an average sneeze will spread over 100,000 virus cells up to 30 feet.

What are the symptoms of influenza and a cold?

The majority of us who think we have suffered from the flu, only probably had a common cold but once you have suffered from flu you will know the difference. If you’re up and about and carrying on with everyday activities you are not likely to be suffering from the flu but a bad cold.

Some of the symptoms of a cold and flu can be very similar, however, flu symptoms come on quickly and more violently whereas cold symptoms will come on gradually.

Symptoms of flu include:

  • Aching muscles.
  • Dry cough.
  • A blocked or runny nose.
  • High temperature.
  • A shivery feeling.
  • Headaches, which can be severe.
  • Sore throat.
  • Loss of appetite.
  • Fatigue and weakness.

Symptoms of a cold include:

  • Runny nose and sneezing.
  • Sore throat.
  • Cough.
  • Slight headache.
  • Slight temperature.

Flu immunization

If a lot of people are infected with the flu at the same time, this is known as an epidemic. Flu epidemics are difficult to predict and can last for a number of weeks. New strains of the flu virus arise all the time and unfortunately immunity against one strain does not protect against other strains. Presently flu vaccinations (only for certain strains) are available at your local health centre but only if you are in a high-risk group such as:

  • Suffering from a chronic chest complaint e.g. asthma.
  • Having heart disease.
  • People who have a lowered immunity due to disease such as cancer or H.I.V..
  • Having chronic kidney disease.
  • People who have diabetes.
  • Elderly – over the age of 75.
  • People living in places where there is a high risk of flu spreading e.g. old people homes.

The best time to be vaccinated is between late September and early November, ready for the winter, don’t wait until there is a flu epidemic. Healthy people don’t need to be vaccinated.

How is flu diagnosed?

Flu diagnosis is mainly from the severity of the sufferer’s symptoms and is often supported by the presence of an epidemic at the time.

What treatment is there for colds and the flu?

If you have got flu, the chances are you think you are dying, but most people recover in a few days and do not need to see a doctor.

Antibiotics won’t make any difference against flu as they act against bacteria and viruses cause colds and flu. The following can help to relieve cold and flu symptoms:

  • Rest and stay at home.
  • Make sure your room is warm and well ventilated.
  • Drink plenty of non-alcoholic fluids, as a high temperature can quickly make you dehydrated.
  • Avoid smoking.
  • Try to eat to maintain energy levels, choose foods high in vitamin C (such as fruit) and carbohydrates (such as pasta and potatoes).
  • Use paracetamol to help reduce fever, aches and pains.
  • Suck throat lozenges or gargle salty water to ease sore throats.

‘Remember’ when using any medicines, check that they are suitable for you before you buy, ask the pharmacist for any advice and read all labels carefully.

Do not rush back into everyday activities as soon as you feel better, you should allow time for a full recovery.

When do I need to see a doctor?

There is usually no need to see a doctor with a cold or flu unless:

  • You are in a high risk group (see above).
  • Your temperature continues to rise and doesn’t settle after a few days.
  • You develop chest pains or become short of breath.
  • You have severe earache.
  • A rash develops.
  • You have a stiff neck.
  • You think you are seriously ill.

Small children and babies are not able to explain their symptoms so parents need to be extra vigilant, if in doubt you should call your doctor.

Are there any complications with a cold or flu?

People with a cold will usually make a full recovery in a few days, but people with the flu can feel awful for a longer period of time.

Complications of flu are mainly from bacterial infections such as pneumonia and normally affect the very young, the elderly or people who are already ill or weak due to a previous illness.

Pneumonia is usually caused by bacteria, and as a result, is likely to respond to antibiotic treatment.

What can I do to prevent getting a cold or flu?

To avoid both colds and flu you should get plenty of exercise, ensure you regularly get a good night’s sleep and eat a healthy diet. Vitamin C, zinc and cod liver oil can help defend your body against infection.

During a flu epidemic you should keep away from crowded places and encourage people with flu to stay at home to avoid infecting others.