Occupational Safety & Health Seminar
The Department of Environmental Health and the Harvard Chan Education and Research Center for Occupational Safety and Health invite you to the next Occupational and Environmental Health Friday Seminar on Friday, October 9, at 1:10-1:50.
Title: Catching the Flu Virus in the Air with a Controlled Human Infection Model
Presenter: Dr. Linsey Marr, University Distinguished Professor and the Charles P. Lunsford Professor of Civil and Environmental Engineering, Virginia Tech.
Location: 502 Kresge or Zoom
Register: Register here to attend via Zoom.
Abstract: Influenza human challenge models, in which participants are voluntarily infected with the virus, provide a unique opportunity to explore aspects of influenza disease and transmission. Traditionally, these models have used intranasal inoculation for safety and reproducibility, although this route does not mimic natural infection. We revisited inoculation with aerosolized virus, which may better mimic natural infection, and found an attack rate of 75%, compared to 85% for intranasal inoculation. Symptoms and viral kinetics were similar between the two routes of exposure. To improve understanding of the potential for forward transmission of influenza, we characterized virus in exhaled breath using a Modular Influenza Sampling Tunnel (MIST), a 3-foot long chamber that allows for deposition of large droplets on cell culture plates and sampling of aerosols at the far end of the tunnel. Participants expelled infectious virus into the air on multiple days post-inoculation. The extent of infectious virus production varied by three orders of magnitude among individuals and was higher during coughing and sneezing compared to speaking. Furthermore, we observed a positive correlation between the total volume of expelled larger droplets and the amount of infectious virus detected. Shedding in respiratory particles correlated with viral load in saliva and nasopharyngeal swabs and with clinical symptoms. Our studies highlight both the power and limitations of controlled human infection model studies and provide an opportunity to explore the complexity of virus expulsion and transmission parameters in a relevant system.
Speaker Information
Linsey Marr
Organizers
ⓘ Harvard Chan School hosts a diverse array of speakers, invited to share both scholarly research and personal perspectives. They do not speak for the School, and hosting them does not imply endorsement of their views, organizations, or employers.