14 DAY TRIAL // It's common knowledge that, when it comes to catching a cold, there is no better time than in winter. Thanks to brainiacs with the Yale University in the US, we now know why this is the case.
In a report in the journal Proceedings of the National Academy of Sciences, specialists with this research facility explain that the rhinovirus, which is the most frequent cause of the common cold, has an easier time infecting people when temperatures drop.
More precisely, the Yale University scientists say that, having carried out a series of experiments in laboratory conditions, they found that the common cold virus more easily reproduces and enters the body when folks' nose cools.
A cold nose makes people more vulnerable to the rhinovirus
Writing in the journal Proceedings of the National Academy of Sciences, the researchers explain that, as part of this investigation, they exposed cells collected from the airways of laboratory mice to the common cold virus.
Of the cells that the scientists toyed with, some were exposed to the rhinovirus while kept at a temperature of 37 degrees Celsius (98.6 degrees Fahrenheit), which is the core temperature of the human body. Other cells were kept at 33 degrees Celsius (91.4 degrees Fahrenheit).
It was thus discovered that, when kept at 37 degrees Celsius, the cells' innate defense mechanisms had an easier time battling the common cold virus and keeping it at bay. At 33 degrees Celsius, on the other hand, the rhinovirus had little trouble replicating and infecting cells.
Hence, the Yale University specialists argue that the reason people more often than not catch a cold in winter is that, during this time of the year, the temperature inside their nose drops, and consequently, the rhinovirus finds it easy to work its way inside the body.
“We found that the innate immune response to the rhinovirus is impaired at the lower body temperature compared to the core body temperature. In general, the lower the temperature, it seems the lower the innate immune response to viruses,” says researcher Akiko Iwasaki.
What this means is that, to keep safe from catching a cold during the harsh winter months, all folks have to do is buy a scarf and use it to cover their nose when venturing outside their home.
Mind you, several other factors are at play
In the report documenting their work, specialist Akiko Iwasaki and fellow researchers explain that, according to their investigations into the matter at hand, the temperature inside people's nasal cavity is not the only factor that influences the behavior of the common cold virus.
On the contrary, the scientists say that, in some cases, the virus can replicate at a rapid pace and infect cells even if exposed to fairly high temperatures. This happens when a person's immune system is compromised and fails to offer protection against the rhinovirus, and explains why some folks catch a cold in summer.