When major disease epidemics strike, airlines are often forced to shut down travel between countries to stop outbreaks from spreading. But a recent study by Florida State University (FSU) researchers shows that changing boarding procedures could drastically reduce transmissions rates.
Ashok Srinivasan, a computer science associate professor, and his team found that the current zoned boarding procedures used by many airlines plays a major role in the spread of disease. To fix the problem, Srinivasan suggests sacrificing some efficiency to reduce clustered contact between passengers.
"There's been a lot of boarding and deplaning research framed in terms of speed and efficiency, but we aren't looking for efficiency. We're looking to decrease the spread of disease," he said. "It turns out that procedures that are generally good at getting people onto a plane very fast are also very bad at preventing infection."
Reducing spread of infection
Using sophisticated computer simulations and algorithms, the researchers analyzed how airline travel procedures affected the spread of infection for major diseases. They found that deplaning tended to be much less dangerous than boarding because passengers weren’t forced to congregate in large groups.
"While deplaning is a fairly fast and efficient process in terms of avoiding the spread of infection, our model shows that boarding the plane is the big problem. When you have many zones, people in the same zone tend to come very close to each other, close enough to easily transmit infections," said Srinivasan.
So, how can we avoid spreading diseases during the boarding process? The researchers suggest that airlines adopt a two-zone system that divides the plane lengthwise and lets passengers board randomly. Doing so, they say, would help reduce the amount of time that travelers are in contact with each other and cut transmission rates.
Worth the wait
In a model of the system, the researchers found that the probability of an Ebola outbreak spreading to 20 new people per month was reduced from 67% under the currently used system to 13% under the suggested system.
"When you have passengers board randomly, people are less likely to spend extended periods of time close to each other," Srinivasan said. "On the whole, random boarding does take longer, but if passengers had to choose between getting Ebola and being seated a few minutes later, we suspect they'd prefer the latter."
"When outbreaks occur, there are often calls for wholesale flight cancellations, but this can harm countries that are already reeling under the onslaught of an epidemic," he continued. "Our research provides insight on the tradeoffs involved in the different policy options. Decision makers need to consider which policies are best, the practical steps that need to be taken and which tradeoffs they're willing to make."