How is slu spread?

A new study has found more evidence that people may catch the flu through airborne particles and not just direct or indirect contact with a person who has the virus.

The study from the University of Maryland School of Public Health also found that when flu patients wear a surgical mask, spread of the virus in even the smallest airborne droplets is significantly reduced.

The study was published Thursday ini the journal PLOS Pathogens.

Our study provides new evidence that there is nearly nine times more influenza virus present in the smallest airborne droplets in the breath exhaled from those infected with flu than in the larger droplets that would be expected to carry more virus," said Dr. Donald Milton, lead author of the study who also directs the Maryland Institute for Applied Environmental Health. "This has important implications for how we prevent the spread of flu."

Researchers, which also included scientists from Harvard and Boston University Schools of Public Health and the University of Hong Kong, collected the exhaled breath from 38 flu patients. The range of viruses people put into the air ranged from undetectable to 100,000 every 30 minutes.

Better understanding of how flu is spread can help with treatment, Milton said.

Routes of flu transmission include: direct or indirect contact with an infected person, contact from a large droplet spray from a cough or sneeze, inhalation of fine airborne particles released through normal breathing and coughing.