According to this article, there were some stowaways of the rodent variety on a recent United Airlines flight from Washington to Beijing. Talk about gross, not to mention dangerous. A snip:
Experts said that mice could spread more than 35 fatal viruses, including plague spot and ship fever. In addition, they might bite circuits of the plane, and cause deadly accidents.
The team also commented that it was very rare to find so many mice on one aircraft.
So, I guess we should all be sure to check the pillows for mouse droppings? Just one more thing to make flying so much fun these days...