Influenza: Attracted to the cold?

The winter season is known for bringing many things: freezing temperatures, snow, ice and for many, the flu. Until now, the reason why influenza erupts primarily in winter has been a mystery.\nA group of scientists in New York recently released a study providing an answer to the age-old question of why the winter season is most likely to bring influenza. The study found that influenza is most effectively transmitted at low temperatures, and is not transmitted at all in higher temperatures.\nKathryn Brown, health educator at the IU Health and Wellness Center, said influenza is a virus that transmits either through droplets from the mouth and nose, through the air or through touching an infected surface. She said the usual symptoms are fever, muscle ache, headache, little energy, dry cough and sore throat. \nPeter Palese, the Horace W. Goldsmith professor of the Mt. Sinai School of Medicine in New York, and one of the scientists involved with the study said the group began working on the study about a year-and-a-half ago when it developed a new animal model to study the transmission of influenza using guinea pigs. \nAfter about a year of work, Palese said the study concluded that influenza is more effectively transmitted at low temperatures around 5 degrees Celsius (41 degrees Fahrenheit), which generally occur in the winter season, but discovered a surprising bit of information as well. \n“We certainly were surprised to find out that no transmission occurs at 30 degrees Celsius (86 degrees Fahrenheit),” Palese said. \nTom Hrisomalos, a Bloomington doctor, agreed that the temperature and humidity in winter is the best environment for influenza to spread. He said the flu rarely transmits in warmer temperatures while it transmits readily in cooler conditions that usually occur from November to March in the Northern Hemisphere. \n“It’s interesting,” Hrisomalos said. “We know there are seasonal illnesses, but the question has always been ‘Why?’”