How Flu Really Spreads
People who have the flu can pass it around just by breathing – no coughing or sneezing required. This news comes from a study showing that droplets of infectious virus breathed into the air by people with flu stay suspended for minutes, even hours.
Researchers at the University of Maryland recruited college age volunteers diagnosed with flu to inhale and exhale into a lab apparatus that allowed measurements of the constituents of their breath. Some of the particles they exhaled were large and loaded with flu virus that fell to surrounding surfaces. Outside the lab the movement of these droplets would make it easy for healthy people to pick them up and contract with flu. Smaller particles proved even more threatening – the U.S. Center for Disease Control and Prevention (CDC) advises that they can stay suspended in the air and spread about 6 feet, potentially landing in the mouths or noses or being inhaled into the lungs of people nearby. The CDC also notes that you’re more likely to pick up the flu this way than by touching a surface contaminated with the flu virus and then touching your mouth or nose. You’re also more likely to inhale the flu virus in gyms or other closed rooms with fogged up windows, a sign that air exchange is inadequate allowing infectious particles to remain, the researchers noted.
My take? These new findings make it all the more important to take common-sense precautions to avoid getting – or spreading – the flu: wash your hands frequently, avoid contact with people who have the flu, keep your hands away from your face and eyes, and if you’re sick, stay at home, drink adequate amounts of fluids and get plenty of rest.
Donald Milton, et al, “Infectious virus in exhaled breath of symptomatic seasonal influenza cases from a college community.” Proceedings of the National Academy of Sciences, January 18, 2018, doi:10.1073/pnas.1716561115
Also in this week’s bulletin: