A computer model that can help airport authorities screen passengers for pandemic influenza has been created by a team of scientists from four national laboratories in the U.S.
Project leader Robert Brigantic says that the novel tool may prove useful in estimating false negatives, people with influenza who slip through the screening process, and thereby help assess the risk of infected passengers unknowingly spreading disease across the nation.
When there is a confirmed human outbreak of a pandemic influenza virus overseas, authorities the US calls for screening of passengers scheduled to fly into the country at international airports, en route screening and arrival screening at ports-of-entry.
However, the efficacy of screening procedures is not known.
This is the reason why Brigantic and his colleagues-including experts from the Washington-based Pacific Northwest National Laboratory, Tennessee-based Oak Ridge National Laboratory, California-based Lawrence Berkeley National Laboratory, and New Mexico-based Los Alamos National Laboratory-have built a computer model of US airport entry screening that combines epidemiology with knowledge about evolving disease states and conditions of passengers over time.
The researchers have tested their simulation under different pandemic scenarios and carried out an analysis of the impact of alternative mitigative, diagnostic and quarantine measures that can be used.
Their results may help decision makers plan for the resources needed at the port-of-entry airports, anticipate possible developments during a pandemic, and devise appropriate courses of action to prevent the spread of disease through the US.
"The simulation work is easily adaptable to model other types of outbreaks, to include non-influenza virus type outbreaks or disease spread," says Brigantic.
The researchers say that there are several key factors that could reduce the risk of a pandemic influenza spreading widely in the US.
They say that passengers should be screened, if possible, before they board a plane bound for the US. They also say that passengers presenting symptoms on arrival should be tested for the pandemic influenza virus and potential quarantine.
According to them, the authorities should be aware that passengers might infect each other before and during their flight, and that any screening program is likely to increase delays and queues.
The researchers suggest that advances are now needed in diagnostics for infection to automate and speed up confirmation.
A research paper on their work has been published in the International Journal of Risk Assessment and Management.