Prior to the new study, little was known about the risks of getting directly infected by common respiratory viruses, such as the flu or common cold, on an airplane, the researchers said.

2019年12月四级真题（第一套）阅读 Section A

That is the conclusion of a new study that looked at how respiratory viruses spread on airplanes.

2019年12月四级真题（第一套）阅读 Section A

Therefore, these new findings should help airplane passengers to feel less vulnerable to catching respiratory infections while traveling by air.

2019年12月四级真题（第一套）阅读 Section A