Wearing Scarves in the Cold Season
A woman wrapped with a heavy scarf uses her mobile phone during snowfall in winter in central Seoul December 12, 2013. REUTERS

Past studies have shown why cold weather or a cool environment induces viral infections in the respiratory system. Cool air in people's nasal cavity is actually more conducive for the common cold virus to multiply than the warm air in the lungs. However, explanation on why viral infection proceeds is not demonstrated. A new research focuses more discussion on how varying body temperatures affect immune reaction instead of virus behaviour. Professor Akiko Iwasaki, an immunobiologist and post-doctoral fellow fellow Ellen Foxman, collaborated with other Yale experts to study the relationship of temperature and immune reaction.

The team conducted tests on mice to compare immune response to rhinovirus (RV) when cells were subjected to temperature ranges of 37 degrees Celsius or the human body temperature and 33 degrees Celsius, which is somewhat cooler. Results show that the immune system's antiviral reaction to rhinovirus is weakened at low body temperature as compared to core body temperature. This strongly implies that innate defence against cold viruses is dependent on varying temperatures and not on the nature of the viral infection. The lower the temperature is, the weaker is the body's antiviral response.

These findings support the age-old notion that using headscarves, mufflers, and other protective clothing to keep the body warm protects oneself from catching a cold. Generally, managing a cold is quite easy nowadays. However, a lot of people with other ailments such as asthma, sinusitis, and COPD find it difficult coping with rhinovirus infection as it aggravates the existing respiratory condition. The Yale research can be used in pursuing related studies in immune response to such ailments.

Rhinoviruses, one of most common cold viruses, causes 10 to 40 percent of the common cold incidence. They are highly active during summer, spring and early fall. Infections caused by rhinoviruses are treated with symptomatic relief and other basic cold remedies. For now, there are no antiviral agents used to treat RV infection. Development of a vaccination is also not viable because of the numerous distinct types of rhinoviruses.

More information on this study can be read in the Proceedings of the National Academy of Sciences.