Still singing “Happy Birthday” when you wash your hands? Yeah, about that…

Early on in the pandemic, we were told that we needed to wash our hands with soap and water for at least twenty seconds. To keep track of time, we’re supposed to sing through “Happy Birthday” once. Seemed helpful. But maybe not.

Scientists at Sweden’s Lund University have spotted a problem. They plotted the trajectories of aerosols ejected by 12 subjects singing different songs to see which ones help spread the virus. They found that songs with lots of consonants sent more droplets into the air.

“Happy Birthday” was especially bad, thanks to the predominance of letters like P and B.

Jakob Löndahl, an associate professor of aerosol technology (who knew there was a such a gig?) says “Different restrictions have been introduced all over the world to make singing safer. [However,] “there has been no scientific investigation of the amount of aerosol particles and larger droplets that we actually exhale when we sing.”

Malin Alsved, an assistant in the study, says “Some droplets are so large that they only move a few decimeters from the mouth before they fall, whereas others are smaller and may continue to hover for minutes. In particular, the enunciation of consonants releases very large droplets and the letters B and P stand out as the biggest aerosol spreaders.”

Singing “Happy Birthday” is still a good time measure for washing your hands. You just might to want to sing in your head, just to be safe.

(Via New York Post)