Common Cold

What is a cold and what causes it?

A cold is an infection of the nose and upper airways caused by a virus. Many different viruses can cause a cold. This is why colds recur, and immunisation against colds is not possible. Children tend to have more colds than adults as adults have built up immunity to many viruses. Adults have an average of 2-4 colds a year. Young children have an average of 3-8 colds a year.

What are the symptoms of a cold?

• The common symptoms are a blocked (congested) nose, a runny nose, and sneezing. At first there is a clear discharge (mucus) from the nose. This often becomes thick and yellow/green after 2-3 days. It may be difficult to sleep due to a blocked nose.
• You may feel generally unwell and tired, and you may develop a mildly high temperature (a mild fever).
• Sometimes there is a mild sore throat, hoarseness and a cough.
• A build up of mucus behind the eardrums may cause dulled hearing or mild earache.

Symptoms typically peak after 2-3 days and then gradually ease off. Symptoms have usually gone within a week, but in some cases they can take three weeks to clear completely. In particular, a cough may linger for up to three weeks, often when other symptoms have gone. The symptoms, particularly cough, tend to be worse and last longer in smokers compared to non-smokers. A child who lives with smokers has an increased risk of developing coughs and colds.

What are the treatments for a cold?

There is no magic cure for the common cold! There is no treatment that will shorten the length of the infection. Treatment aims to ease symptoms whilst your immune system clears the virus. Note: antibiotics do not kill viruses, so are of no use for colds. The most useful treatments are:

• Paracetamol or ibuprofen which will ease fever, sore throats, aches and pains.
• Make sure you drink enough or give your child plenty to drink. A fever may cause you to lose extra body fluid by sweating. This may lead to mild dehydration which can make you feel more tired, and may cause a headache. Hot drinks are often soothing too.
• A steam inhalation may help to 'clear the nose'. It has a temporary effect, but may be useful before bedtime to help you get off to sleep. However, beware of scalding yourself if you use hot water. A hot steamy shower is perhaps the safest option.
• A menthol sweet may also clear a bunged up nose for a while.
• Saline drops is a popular treatment for a bunged-up nose in a baby. Consider putting a few drops of saline (salt water) into the nose just before feeds. Some people feel that this helps to clear the nose to make feeding easier. There is little scientific evidence as to how well this works, but it may be worth a try if feeding is difficult. You can buy saline drops from pharmacies.

What about cold remedies?

You can buy many other 'cold remedies' at pharmacies. There is little evidence that they do much good, but some people find them useful. For example, a decongestant nose spray may help to clear a blocked nose.

But remember, cold remedies often contain several ingredients. Some may make you drowsy. This may be welcome at bedtime if you have difficulty sleeping with a cold. However, do not drive if you are drowsy. Some contain paracetamol, so be careful not to take more than the maximum safe dose of paracetamol if you are already taking paracetamol tablets.

In March 2009 an important statement was issued by the Medicines and Healthcare products Regulatory Agency (MHRA) which says:

"The new advice is that parents and carers should no longer use over-the-counter (OTC) cough and cold medicines in children under 6. There is no evidence that they work and can cause side effects, such as allergic reactions, effects on sleep or hallucinations.

For 6 to 12 year olds these medicines will continue to be available but will only be sold in pharmacies, with clearer advice on the packaging and from the pharmacist. This is because the risks of side effects is reduced in older children because they weigh more, get fewer colds and can say if the medicine is doing any good. More research is being done by industry on how well these medicines work in children aged 6-12 years."

Note: paracetamol and ibuprofen are not classed as cough and cold medicines and can still be given to children.

A note of caution

If you do use a decongestant nasal spray, do not use it for more than a few days. It can have an immediate effect to clear a blocked nose. However, the effect does not last very long. But note: if you use one for more than 5-7 days, a 'rebound' severe congestion of the nose may develop.

Some recent research developments

Research studies suggest that:

• Some preparations based on the herb of Echinacea purpurea (a herbal remedy) might decrease the severity of cold symptoms in adults.
• Zinc sulfate appears to reduce the severity of the cold symptoms in healthy children. However, it has no effect on the duration of cold symptoms.

It is not clear if these are likely to become routine treatments or if they are still in the realms of research. See the references at the end for details of these.

Are there any possible complications from a cold?

Most colds do not cause complications. A cold may trigger coughing, wheezing and shortness of breath in people with asthma or other lung diseases. Sometimes the infection travels to the chest, sinuses, or ears. Bacteria may thrive in the mucus so some people develop a 'secondary' bacterial infection of the chest, ears or sinuses. Therefore, consult a doctor if symptoms do not start to ease within a few days, or if you suspect that a complication is developing. In particular, symptoms to look out for that may mean more than just a cold include:

• Fever, wheezing or headaches that become worse or severe.
• Fast breathing, shortness of breath, chest pains, or if you cough up blood.
• Stridor (noisy breathing), or difficulty breathing - especially in a child.
• Unusual irritability or persistant crying in a baby.
• Persistent earache.
• Drowsiness or confusion.
• A cough that persists longer than 3-4 weeks.
• Any symptom that you cannot explain and you are concerned about.

Can colds be prevented?

Prevention is difficult. Many viruses can cause a cold. This is why it is difficult to produce a vaccine. Also, many viruses that cause colds are 'in the atmosphere' which you cannot avoid. However, the following are sensible suggestions that may minimise the risk of 'catching a cold' or of passing one on if you have one:

• People with colds should not get too close to others. For example, kissing, hugging, etc.
• If you have a cold, wash your hands often with soap and water. Many cold viruses are passed on by touch, especially from hands that are contaminated with a cold virus.
• Avoid sharing towels, flannels, etc if you have a cold, or with anyone who has a cold.
• For children, discourage the sharing of toys belonging to a child with a cold. If your child has a cold, consider washing toys with soapy water after use.

Basically - it is common sense and good hygiene that may prevent the passing on of some colds.

There is no good evidence that vitamin or mineral supplements can prevent the common cold.