According to ‘Cattle Car Syndrome’ Offers SARS Insights, humans packed into airplanes resemble livestock packed into cattle cars:
Packed into cattle cars, young animals destined to be fattened up in feedlots get a disease called shipping fever. They develop cough, pneumonia and drip mucus from their eyes and noses.It is caused by a coronavirus, the same class of viruses as the SARS virus, and the symptoms resemble those of SARS.
The conditions that can bring about shipping fever are similar to those affecting the travelers who spread SARS around the world, says Linda Saif, a professor of food animal health at Ohio State University.
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Two human coronaviruses cause about 30 percent of common colds, but the viruses cause more significant diseases in pigs, chickens and other livestock.