• Humidity and the Flu

With the help of a local preschool Mayo Clinic researchers may have found a way to slow the spread of the seasonal flu, according to a new study in the journal PLOS One.

Researcher and senior author Chris Pierret, Ph.D., who is part of Mayo Clinic's Center for Clinical and Translational Science, says, “Within this study we were able to show significant reduction in influenza virus survival and infectivity through the humidification of nursery school classrooms during the driest month of winter. This could be a big deal, not only to schools, but to businesses and homes.”

Previous work suggests that seasonal flu cycles in the United States are linked to population density of children aged three to four. Also, research has shown that low absolute humidity correlates with greater flu infection, such as the Minnesota winter. The Mayo Clinic-based study applied that knowledge to a classroom full of children.

Dr. Pierret’s group predicted and found that by increasing a classroom’s humidity, they could limit the flu’s ability to survive on surfaces and its ability to infect people, as compared to non-humidified rooms.

Funded in part by the Center for Clinical and Translational Science, the study is relatively small, comparing two humidified to two non-humidified rooms in one school. But it serves as a proof-of-principle for controlling the seasonal flu beyond the typical suggestions such as vaccination and hand-washing.

When asked what he will do next, Dr. Pierret said “The nature of virus transmission in the air is quite complicated, dependent on airflow in a room and changed by all activities of those in the room. We are currently building new partnerships to better resolve the potential for humidification as a flu intervention in the complex spaces in which we live.”

Dr. Pierret’s group was able to form a partnership with the local Aldrich preschool for the study, involving both parents and teachers in the planning phase of the experiment. Kevin Ewing was the Director at Aldrich for the duration of the experiment. When asked what it was like to be an active participant in planning the study, he said “I really enjoyed the project; it really was getting back to the Aldrich-Mayo Clinic roots.”

Notably, Aldrich Memorial Nursery School was established by the Mayo Foundation in 1944 under a different name. It was developed as a place to study childhood development using the lessons of Mayo Clinic-based pediatrician Benjamin Spock, M.D., author of The Common Sense Book of Baby and Child Care fame. This study continues the long legacy of Mayo Clinic researchers working with the local community.