Researchers Discover When Flu Risk Is Highest
According to the Centers for Disease Control and Prevention (CDC), flu activity in the U.S. is increasing at this time, and the 2016-2017 flu season is expected to be worse than last year's. The CDC reports that outpatient visits for influenza-like-illness are currently above normal, and activity is expected to increase further in the weeks ahead.
A new study, conducted by researchers in Sweden, has identified a link between cold weather and the spread of flu viruses and a weather pattern that increases flu risk. A 3-year study shows that seasonal flu outbreaks in an area begin each year about one week after the first cold spell—below freezing temperatures and low humidity for a period of days.
This pattern was also seen in some other respiratory viruses, including respiratory syncytial virus (RSV) and coronavirus, but not in others, like rhinovirus, which causes the common cold. According to researchers, while a sudden spell of cold weather can "kickstart" a flu epidemic—which then continues independent of the weather—it's certainly not the only factor involved.
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