The temperature difference between the average nose and the lungs may be the reason people first acquire a cold (rhinovirus) in their nose before the infection spreads to other parts of the respiratory system. Akiko Iwasaki from the Yale University School of Public Health and colleagues are the first to demonstrate a direct relationship between nose temperature and the potential to catch a cold. The research was published in the edition of the journal Proceedings of the National Academy of Sciences.
The average temperature in human lungs is 98.6 degrees Fahrenheit. Depending on the external environment, the average nose has a temperature of 93.2 degrees Fahrenheit. Previous research has demonstrated that the common cold multiplies faster and more efficiently in the cooler temperatures of the nose.
The researchers examined the rate of replication and the relationship to temperature of a mouse rhinovirus and the epithelial cells in the nose, throat, and lungs. The natural antiviral response was found to be more active at higher temperatures. The result is not particularly amazing because the activation of antiviral response is a chemical reaction. All chemical reactions proceed at faster rates at higher temperatures.
The discovery is significant in preventing colds in humans. The preventative could be as simple as keeping the nose warmer during peak cold seasons. A warmer nose would produce a less hospitable climate for the cold virus to multiply.
The researchers do not make any claim that higher nose temperatures can prevent the flu. The advent of a new strain of epidemic flu in the United States would be an impetus for further study of nose temperature and flu virus contagion. The antiviral response to flu is similar to that produced from cold viruses and a warmer nose might assist the flu vaccine in preventing flu.