Surprising Things You Didn't Know About Colds

Most people have caught the cold many times in their lives, yet most of them don't actually know much about the cold. You may know the basic symptoms of them but what do you really know? There are many facts about the cold that surprisingly few people know about and many myths that a lot of people do believe. If you're interested in knowing more about the cold then keep reading. You might even learn something new.

Cold weather isn’t the cause of colds

Yes. That's correct. Though many people believe that cold weather causes colds, this, in fact, is not true. You may be wondering why we're more likely to suffer from the cold during the winter, if it isn't because of the cold weather, what causes it? Well it's not exactly fully understood by sci not sure it’s still fully understood, but there are a couple of good theories. 

The first is that droplets of infected mucus expelled from someone when they sneeze or cough, travel faster when the air is drier.  This is because the droplets dry out, becoming smaller and lighter and so fly through the air more easily. The theory goes that in cold weather the air is less humid, the droplets travel further and are more likely to be breathed in by some other unfortunate person. 

The other effect of dry air is that it dehydrates the normally moist mucous membrane lining the nose. This is part of our defence mechanisms – inhaled virus particles are trapped in the moist lining and washed away by nasal secretions. 

Warm noses protect best

The second theory is all to do with the cold nose we experience in cold weather.  The first line of defence against viruses we breathe in is the rich blood supply in the lining of our nostrils and respiratory passages.  Immune cells in the lining are able to catch and hold the virus particles which are then washed out with nasal secretions.  

Hence some viruses are able to gain entry to cells in the respiratory passages, and cause an infection.

The connection between long-haul flights and colds

Winter isn’t the only time we’re exposed to dry air – air-conditioning in hotels and offices, and in airplane cabins, has also been blamed for causing colds.  This is probably by the same mechanism as in winter – the dry air dehydrates the nasal lining which is then less effective at trapping inhaled virus particles.

Also, with a large number of people confined to a small space for long periods of time, it is inevitable that infections will be passed on, especially when they are as easily transmitted as cold and flu viruses.   

In addition travellers on long-haul flights are often deprived of sleep which lowers immunity, allowing infections to flourish.

The cold virus travels further than you think

When someone with a cold sneezes or coughs they expel mucus droplets containing virus particles, which are able to infect another person if breathed in or touched. 

Most experts agree that the most infectious time is when symptoms are at their height, so the lesson from this is not to get too close to someone with a cold and be sure to quickly turn your head the other way if they sneeze or cough.

Pandemic Influenza – Be Careful What You Touch

The even more worrying news is that it’s not just other people’s coughs and sneezes you need to avoid. 

These objects include anything an infected person has touched – just look around you now at all the things this might include.  Table tops, taps, door handles, light switches, desks, computers, pens………… the list goes on.

It is thought that the virus particles are passed on by people coming into physical contact – for example by shaking hands – or by touching contaminated objects.  The virus then gains entry to the body by contact between the contaminated hand - and the eyes or nose.

This method of transmission is likely to be another reason why many people get a cold following a long-haul flight. In a passenger plane, hundreds of people touch surfaces such as seats, trays, cups, locker handles. 

The advice is to wash hands or use a hand sanitizer frequently on flights and avoid rubbing your eyes or touching your face.

As a result of this knowledge there was recently a ‘Bin it!’ campaign in the UK. The advice given to people with colds was to immediately dispose of tissues into which they’ve sneezed, or blown their nose; and to wash their hands afterwards.  If everybody carried out this advice it would help to reduce the spread of colds and flu around homes and offices.

Cold and flu viruses keep changing

Whenever you suffer a cold or flu, if you have a normal intact immune system, you will develop immunity to that particular strain.  You will have developed antibodies to it, so that next time it is encountered your body will recognise it and immediately mount an ‘attack’ so that it will not be allowed to cause an infection.

So how come we go through our whole lives having colds and/or flu?  

So we’re always encountering new ones.

But not every contact ends up in a cold

Because cold and flu viruses are so common and around us all the time, it is estimated that we are actually infected many more times by cold and flu viruses than we actually know. But only a small proportion end up giving us the characteristic symptoms of a cold or flu.

The other times are called subclinical infections – in other words they do not result in a clinical – measurable or observable – illness. Sometimes we may feel a little more tired than usual or not quite ourselves - as if we are going to come down with a cold - but symptoms never actually develop.