Colourful leaves and gorgeous sunsets – autumn is simply beautiful, right? Unfortunately, this season also has a downside: it is the time when everybody seems to be falling ill. Each one of us has probably experienced the feeling of sneezing ten times during an important meeting. Therefore it seems appropriate to ask: why do we become ill and what are the ways to protect ourselves from colds?
The common belief that a cold is caused by “catching a cold” is not true. Common colds are caused by viruses which infect the nose and throat mucosa (the upper respiratory tract). There are many of these viruses, but the most common ones to cause a cold are rhinoviruses. And the “good news” is – there are more than a hundred different types of them! The great number of different viruses is the reason why people become ill with colds again and again.
A cold develops when people are infected with a virus to which they are not yet immune. Grown-ups have colds less often than children because they have suffered from many viral infections already and have developed the necessary antibodies which prevent them from getting sick again. Children who are younger than six months also experience colds less because they are protected by the antibodies which were transferred from the mother to the foetus during pregnancy. These antibodies disappear from children’s blood over time, though.
After being infected with a virus, it usually takes 12 hours to 2 days for a cold to develop. Sometimes the illness might even have a week-long incubation period. Bear in mind that a person becomes infectious to other people already during the incubation period – so a person who seems to be perfectly healthy, could actually be infectious.
People who have a cold are most infectious to other people at the very beginning of the illness. Those people should treat themselves at home if possible but if there is no fever and the overall feeling is satisfactory, it is alright to go to work with rhinitis and a cough. When doing that, one should still bear in mind that viruses are transmitted via droplets when people cough and sneeze. In order for the infection to transmit, the distance between a sick and a healthy person needs to be less than one metre. So if you do not want to infect another person (and we hope you don’t!), keep a short distance between the two of you when you are experiencing the symptoms of a cold.
The good news is that a common cold is a self-resolving disease. It means that sometimes all the symptoms retreat within a day or two, but a full recovery mostly requires a bit more time. The risk of getting a cold can be reduced with very simple methods – such as washing hands carefully several times a day, spending much time out in the fresh air and airing the rooms properly.
Viruses are actually often transmitted via hands and items (e.g. handles, toys, bank notes) because viruses can survive on hands and surfaces for hours and days. Therefore, an ill person should cover their mouth with a sleeve or a handkerchief when coughing and sneezing instead of using their palm or fist. In the latter case the viruses can be easily be picked up by hands.
It cannot be stressed enough that washing hands should be taken seriously. Hands should be washed with water and soap, rubbing them together for half a minute and then dried carefully using a disposable towel if possible. Also, if possible, hands should be washed every time after blowing your nose and coughing. In case of a direct contact with a coughing person with a runny nose, avoid touching your eyes, nose and mouth until you have the chance to wash your hands.
There are no miracle medications for colds but the symptoms (stuffy nose, headache, muscle ache etc.) can be alleviated with over the counter medications available at pharmacies. Multivitamins and red rudbeckia do not significantly reduce the risk of getting a cold, but taking probiotics might reduce the risk somewhat. Moderate consumption of garlic and ginger does not hurt either!
Marje Oona is an Associate Professor in Family Medicine at the Institute of Family Medicine and Public Health at the University of Tartu.