Air, water, clothing and insects are all means of infection.
空气、水、衣服、及昆虫都会成为疾病的传染媒介。
《新英汉大辞典》
2
Air travel itself carries only very minimal risks of infection with TB of any kind.
航空旅行本身只具有极小的感染任何类型结核的风险。
3
These are risks like HIV infection, malnutrition, diabetes, smoking, alcohol and substance abuse, indoor air pollution and, above all, limited access to basic care for the poorest people.