Four major US national laboratories have worked together to develop a computer model to help airport authorities screen passengers for pandemic influenza. The tool can detect false negatives, people with influenza who slip through the screening process, and so cut the risk of infected passengers unknowingly spreading disease across the nation.
During a confirmed outbreak of a serious virus overseas, the US National Strategy for Pandemic Influenza insists on screening of passengers scheduled to fly into the US and at US arrivals. How well this works was an unknown and so researchers have developed a computer model, to simulate US airport entry screening that combines epidemiology with knowledge about evolving disease states and conditions of passengers over time.
In the original work the team assumed that a pandemic disease would have an origin in Asia, which was based on contemporary thinking that this would be the most likely origin for an avian influenza type pandemic. Of course, the recent swine flu (H1N1) outbreak in Mexico emphasises that a new disease could emerge almost anywhere. I asked the team leader Robert Brigantic at the Pacific Northwest National Laboratory, in Washington, whether the H1N1 outbreak confounded their studies.
“It is a fairly straightforward process in our methodology to move the outbreak origin to any geographic location,” Brigantic assured me, “Indeed, based on the fact that the origin of the next pandemic is uncertain, in follow-on work to be conducted for the Centers for Disease Control and Prevention (CDC), we would look at various pandemic origins to include Mexico, Europe, Africa, and other origin points.”
He adds that the simulation work is easily adaptable to model other types of outbreaks, to include non-influenza virus type outbreaks or disease spread.
Robert Brigantic, and colleagues at the Pacific Northwest National Laboratory, in Washington, and teams at Oak Ridge National Laboratory, Tennessee, Lawrence Berkeley National Laboratory, California, and Los Alamos National Laboratory, New Mexico, report details of their simulations in the current issue of the International Journal of Risk Assessment and Management.
Robert T. Brigantic, John D. Malone, George A. Muller, Russell Lee, & Jim Kulesz (2009). Simulation to assess the efficacy of US airport entry screening of passengers for pandemic influenza Int. J. Risk Assessment and Management, 12 (2/3/4), 290-310