Misconception Busted: Low Temperature Doesn’t Directly Cause Cold, Flu

Only a pathogen like bacteria and viruses can cause an infection

From our old childhood days, if there is one notion that many of us have picked is that cold weather can make us sick. Each one of us has heard our loved ones saying things that if we step outside in the chilling air, we will catch a cold. We might get a similar response when we might express the desire to have ice cream in the cold season. While to some extent it might be true but interestingly, the weather directly does not affect our body. However, lower temperatures can make us more prone to certain illnesses such as colds and flu.

The notion that temperature itself is the primary causative agent for sickness might be partly incorrect as it only facilitates the spread of viruses and can make us more prone to upper respiratory infections. As per experts, the correlation between cold weather and cold is not biologically understood by many people. They might know there is a connection but might not know how it happens.

Some recent studies have shown that cold temperatures can lead to a decline in the immune response of nasal activity. Other factors prompt the easy spread of certain viruses such as rhinovirus and other influenza-causing pathogens.

Declining nasal immunity in winters

A study published in the Journal of Allergy and Clinical Immunology shows that just a temperature drop of 5 degrees C can reduce the immune response just by half. The nose is the gateway for the virus to make an entry into our body. There are special fluid-filled sacs released in the nasal cavity that is known to protect the mucous membrane of the nasal cavity and prevent the virus to infect the cells. These extracellular vesicles (EVs) kill the bacteria before they can cause serious illness in the system. The study observed that by reducing the temperature, the number of EVs released reduced significantly and so did the innate immune response of the nasal cavity. This facilitated the virus to stick better on the membrane and cause severe infection if not opposed.

Also, viruses survive better and reproduce more easily in low temperatures. Dry air also facilitates the spread of these viruses. Due to a weakened nasal response, the nasal cavity might remain dry which makes it easy for the virus and other pathogens to take entry into the body.

Staying indoors is another problem

Going outdoors is not comfortable during winter. Most people try to spend time inside their houses. If the spaces you live in lack adequate ventilation, you might be at a greater risk of breathing in the aerosols of those infected with the common cold. Your physical proximity to infected persons also increases during the cold season which eases the transmission.