In a new study destined to amplify the paranoia of those already bacteria-phobic individuals, a team of scientists has found evidence revealing the influenza virus is more easily transmissible that previously thought. Contrary to commonly held beliefs the virus was shown to be passed on to others simply through exhaled breath.
"We found that flu cases contaminated the air around them with infectious virus just by breathing, without coughing or sneezing," says Donald Milton, lead researcher on the study.
The University of Maryland-led study set out to examine how the virus is transmitted by capturing exhaled breath from 142 subjects suffering from influenza. Samples of exhaled breath were taken from each of the subjects across four potential modes of transmission: natural breathing, talking, coughing, and sneezing.
The frightening results found a presence of infectious virus in 39 percent of samples taken from subjects during natural breathing. While coughing was obviously a prevalent cause of infection in the study's observations, sneezing was only rarely observed and the presence of detectable viral RNA in a sneeze was not greater than that of a cough. It is suspected that the larger aerosol droplets generated by a sneeze could contribute to greater surface contamination.
"People with flu generate infectious aerosols (tiny droplets that stay suspended in the air for a long time) even when they are not coughing, and especially during the first days of illness," says Milton. "So when someone is coming down with influenza, they should go home and not remain in the workplace and infect others."
A 2013 study from the same team found that wearing a surgical mask significantly reduces the transmission of influenza via airborne droplets. So it doesn't really matter if you aren't coughing or sneezing, you still are effectively transmitting the flu to others just by breathing near them unless you wear a mask.
The new study was published in the journal PNAS.
Source: University of Maryland