1918 influenza pandemic origin in Chinese laborers/soldiers: Medical historical analysis

To the Editor,

The recent article on “1918 influenza pandemic origin in Chinese laborers/soldiers” is an interesting publication.¹ This is an exact medical historical analysis, which is a type of research rarely seen in medical literature. Shanks¹ mentioned that there was “no evidence of 1918 influenza pandemic origin in Chinese laborers/soldiers in France” and noted that “this finding does not support a Southeast Asian importation of lethal influenza to Europe in 1918.”. Most certainly, when working with the various tools associated with historical research, it is very hard to control the reliability of the available records. For example, if there is an indication of “no record”, that does not necessarily mean there has been no case. In the present day, the problem of underreporting remains commonplace.² Nevertheless, if we consider the natural history of influenza and relate it to the situation as it existed in 1918, we might find some areas of concern. In 1918, the overall transportation system was poor, and it took many weeks to travel from China or Southeast Asia to Europe. Based on the fact that influenza has a short incubation period (less than 1 week),³ it is unlikely that the illness first appeared in Europe. In the past, the occurrence of worldwide pandemic infection seemed to involve more barriers to transmission and thus was more difficult to spread than in the present day.