Wu Yu-hsing [Wu Youxing; 1582-1652 A.D.] -- Wu developed the concept that some diseases were caused by transmissable agents, which he called liqi (pestilential factors). His book Wenyi Lun (Treatise on Acute Epidemic Febrile Diseases) can be regarded as the main etiological work that brought forward the concept, ultimately attributed to Westerners, of germs as a cause of epidemic diseases.
