Nice day at the coughice? How to avoid winter germ warfare

Once you manage to escape this germ warfare, the IT guy, covered in cold sores, comes to help you with an email issue. Then there's the canteen staff to contend with - you've never seen mucus like it.

Worse still, even if you survive the microbial death trap that is the office, it doesn't make you immune to a crowded party afterwards or the journey home.

Being squashed together in a packed Tube carriage with the disease-ridden public will guarantee you won't escape uninfected this winter.

Yes, it's that time of year when coughs and colds abound, and my surgery is overrun with patients complaining of chest infections or coughs that won't go away.

Most are caused by viruses. There are more than 200 different types that can cause the common cold, so over the course of a lifetime you can expect to encounter them on a regular basis.

Coughs and colds occur more frequently in the colder seasons for several reasons.

Falling temperatures mean we tend to stay indoors more, often in enclosed and busy places where conditions for the transmission of infectious microbes are optimal.

At these times of year, the mucous membrane in the nose can get dry, losing many of the protective properties that would normally stop microbes from entering the respiratory tract.

The drying effect of cold weather can also cause damage to the mucosal cells, again facilitating the entry of viruses.

Interestingly, cold viruses are also more stable in cooler, dry climates. The protective envelope that encapsulates them is stronger at colder temperatures. When the weather warms up, this protein shell is more prone to "melting" and damage.

What is not true, however, is that the human immune system will somehow get weaker once the weather gets colder.

Research has not found any difference in immune function at high or low temperatures, though it is possible to catch a different strain of virus straight after getting over a previous one, which is often the reason why people claim their immune system is weaker.

While most coughs clear up within days, around 20 per cent become chronic and some can persist for years. It does seem that at the moment there are several viruses around that follow this more chronic pattern.

As a general rule, your doctor should properly investigate any cough lasting longer than eight weeks.

Meanwhile, there are other causes of chronic cough besides viruses.

Post-nasal drip can cause an irritating, tickly or dry cough with a sensation of mucus dripping down the throat.

It may last for years and cause the throat to become sore and swollen. Overactivity of the mucus glands that line the nose and sinuses is the cause, often stimulated by allergies or viruses.

For Londoners, a pollution cough is also a real possibility. Usually characterised by a constant phlegmy cough that is often worse in the early morning, it can be much more noticeable in winter.
This condition can be helped by techniques that increase lung capacity - usually exercise, but steam inhalation and humidifying rooms can also help.

Some coughs are not really lung- related at all. One in 10 people experience acid reflux at some point in their lives, which irritates the sensitive lining of the oesophagus and the back of the throat, causing the typical loud, harsh cough and sometime a hoarse voice too.

The main cause for the majority of our coughs, however, is the common cold virus. It is easily spread and difficult to avoid.

Dramatic gestures such as wearing a face mask are unlikely to help much as most people pick up infections from contaminated surfaces rather than from droplets in the air.

Scrupulous hand hygiene is probably the most effective way of reducing your chances of getting sick, especially after using public transport.

Something we would do well to get over is our foolish attitude to being ill. If you are sick, stay at home.

Struggling into work when you are ill is not valiant and dedicated, it is foolish and will only prolong your own illness and virtually guarantee that colleagues will catch your virus too. Stay home and recuperate.

Medical science has been of virtually no help when it comes to treating the cold bug.

Many people swear by their own remedies, but no conclusive data has shown that large doses of vitamin C prevent colds, though it may reduce the severity or duration of symptoms. And the jury is still out on zinc - as many studies have shown it is effective as have shown that it is not.

The best way of helping to suppress a troublesome cough, particularly at night, is to take medicines containing the painkiller codeine, which suppresses the cough reflex in the brain - but, of course, only do so under your doctor's supervision.

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