The first case of this plague occurred in Fujiadian, and soon spread in Harbin, even to the whole northeast region. The Qing government attached great importance to the epidemic situation. Lian Dewu was ordered to lead the epidemic prevention work in Northeast China, and Lian Dewu came to Harbin, where the epidemic was the most serious. At that time, people's thoughts were feudal, and it was unacceptable to dissect a corpse. In order to get the real cause, Lian Dewu secretly dissected a Japanese woman who died of illness, and determined that this large-scale epidemic was pneumonic plague, which spread through breathing and droplets. Lian Dewu suggested controlling the spread of diseases by controlling traffic and isolating epidemic areas. He also researched and invented a mask, which has the function of isolating virus, isolating and wearing a mask to prevent infection, much like the current epidemic prevention measures. It can be seen that under the condition of poor medical conditions at that time, the method proposed by Lian Dewu was very scientific and correct.
Although the epidemic prevention method proposed by Lian Dewu was good and the epidemic situation was alleviated, Lian Dewu faced a large number of dead bodies and realized that these bodies might become a huge source of infection, so Lian Dewu boldly proposed cremation of the bodies. In feudal society, this practice is very bold. With the support of the Qing government, Lian Dewu cremated a large number of bodies, which broke through the traditional concept of people at that time, completely eliminated the source of infection of the virus and controlled the epidemic.
Although Lian Dewu took very effective measures to control the epidemic, due to the limited medical conditions and materials at that time, and the lack of awareness of many medical workers, many medical workers were still infected and sick in this epidemic prevention work, and they died gloriously in their jobs.