Ouyang Xuan summed up the current state of the Thunderbolt Army in one sentence, that is, politically dormant, militarily active defense, and economically vigorous. During the confrontation between the soldiers and the other river on the front line, the rear of the Perak Army was not idle. The construction of the first phase of industrial and mining in Pengzhou and Jiading Province is nearing completion, with dozens of new coal, iron, limestone, sulfur, nitrate, and lead mines being opened respectively. The copper mining energy of Jiufeng Mountain has been restored, and the first copper ore has been mined in the mountains near Runeterra, but the production is not much. With the large-scale mining of the mine, a large number of factories such as sulfuric acid plants, smelters, and foundries have also been put into operation, and the most important ones are Pengzhou and Jiading arsenals.

Although there are many industrial and agricultural production affairs, Ouyang Xuan did not invest too much energy in government affairs, on the one hand, the government affairs team led by Li Shuang is very dedicated and does not need him to worry too much, on the other hand, it is also because there are a large number of experiments waiting for him. Although Ouyang Xuan has guided the direction and path of scientific research, but the details involved need to be repeatedly tested and verified, after Yang Hui is in charge of the research institute, he will save a lot of worry in the future, but he can't let go at the moment. One is that Yang Hui's vision and concept still need to be improved, after all, there is still a gap between him and Ouyang Xuan, who has been trained in modern science, on the other hand, his expertise is actually narrow, "there is a specialization in the art industry", he is good at mathematics and science and engineering technology, but he lacks knowledge of chemistry, medicine and other aspects. Chemistry is Ouyang Xuan's strength, and he is also involved in medicine. Of course, in terms of clinical medicine, Ouyang Xuan is a layman, and all he knows is preventive medicine knowledge.

During the confrontation between the Perak Army and the Mongolian Army, Ouyang Xuan had to spend part of his time guiding the chemical experiments of the Academy of Sciences in addition to handling military affairs, and the rest of his energy was devoted to health and epidemic prevention, so that he had very little time to go home. Of course, there was no one back home, and although Yang Yan was five months pregnant, she was still dragging her big belly to deal with the affairs of Nanyang Company. After the headquarters of Nanyang Company has been moved to Chengdu, although Ran Zhong is in charge there, Yang Yan still needs to go once in ten days and a half months to deal with important affairs, and she and Ouyang Xuan still get together less and leave more. Seeing this situation, his brother-in-law Yang Bangxian often sighed and said that the chemical laboratory of the research institute, the conference room of the medical school and the staff department are the home of his brother-in-law, and the home on the island in the middle of the river is just an inn.

At present, the medical school has cultivated penicillin in the laboratory under the guidance of Ouyang Xuan, but there is still a long way to go before large-scale production. On the one hand, there is a lack of conditions for industrial production, not to mention the immaturity of purification technology, and even the equipment for large-scale cultivation of strains cannot meet the standard, on the other hand, there is the problem of production process and cost, and the current price of production is even far more than gold. Ouyang Xuan understands that the progress and iteration of technology takes time, and it also needs the improvement of the industrial base, and it is not in a hurry. From ancient times to the present, the greatest damage to the economy and society is the plague, which is what Ouyang Xuan called an infectious disease. In fact, the direct killing of the population in war is a drop in the bucket compared to the famine and plague that followed. Now that the Thunderbolts have solved the problem of hunger, the next step is to focus on the control and prevention of infectious diseases.

Ouyang Xuan and Tang Shun focused on the prevention and treatment of infectious diseases: smallpox, cholera, and plague, the three most severe diseases. Before these three diseases was malaria, but it was cured by Ouyang Xuan with the juice extracted from Artemisia annua. These three diseases are highly contagious and have high mortality rates, and often bring catastrophe to a region. The Mongols brought the "Black Death" to Europe on their western expeditions, and several outbreaks killed tens of millions of people and almost destroyed European civilization, and the Black Death was the bubonic plague. The same was true of smallpox, which was feared by the Spanish colonizers, and the Indian civilization was destroyed by smallpox, flu and other diseases brought by the Spanish colonizers. Although cholera is not as dangerous as the first two plagues and has a slightly lower fatality rate, it also has more frequent outbreaks and frequent transmission routes, and its vomiting and diarrhea often pollute water sources. The most effective way to deal with infectious diseases is prevention, not treatment, and in fact there is no specific cure for these three infectious diseases. Therefore, at the seminar on the prevention and control of the plague, Ouyang Xuan proposed three ways of prevention and control: eliminating the source of infection, cutting off the transmission route, and treating the symptoms.

When the Thunderbolts attacked Pengshan City, cholera broke out in the city. Under Ouyang Xuan's order, all the residents in the city were moved to a small ravine for isolation and symptomatic treatment, and the inside and outside of the city were thoroughly disinfected, so that the epidemic was controlled within a certain range and the mortality rate was greatly reduced. On the basis of summarizing the gains and losses of this experience, Tang Shun, with the strong support of Li Shuang and Lu Dezhi, vigorously promoted the publicity of environmental remediation and personal hygiene, and even issued a decree that if the hygiene is not up to standard, he will be punished for short-term hard labor, forming an atmosphere in which everyone stresses hygiene. In Perak military territory, it is considered extremely unseemly to go out unkempt or have fleas on your body. This response proved to be effective against cholera, and there were occasional outbreaks in the Perak area, but they were quickly extinguished.

In addition to this, the Thunderbolts also have a large number of cats. The main body of the Thunderbolt Army granary is made of wood in order to prevent moisture, and the rest is made of cement slurry, which is very strong, but it still cannot withstand the bite of rats day after day, and cats can take back valuable food from rats. Ouyang Xuan personally ordered the cat because rats are the host of Yersinia pestis and the source of mobile infection. The steppe area where the Mongols were active was a high incidence of plague, and the Mongol cavalry moving south also brought the source of infection to Han China. What's even more odious is that the Mongolian army often uses biological warfare in warfare, that is, the corpses of the sick and dead are thrown into the enemy's city army with trebuchets to pollute water and food, so as to achieve the goal of victory without a fight. In fact, on the Mianshui front, after the plague broke out in Yang Wen'an's department, the Mongolian army also tried to throw the corpses of the newly attached troops who died of illness over, but they were thwarted by the Thunderbolt army.

To deal with the smallpox virus, the vaccinia inoculation method proposed by Ouyang Xuan is the best means of prevention. Because vaccinia virus and smallpox virus share cross-reactive antigens, they can induce autoimmunity to prevent smallpox. This technique is to remove pus and scabs from smallpox-infected cattle and inoculate them into healthy people to gain immunity. In fact, the Thunderbolts developed this technology as early as last year, and the soldiers and technicians that Yu Zhu brought to Liuqiu were the first to be vaccinated. However, there is a shortage of cattle in the Perak Army, not only for arable land but also for power in mines and factories, and there is really not much cattle to use for extracting vaccines. Cattle are an important strategic commodity, but they are much easier to buy than war horses, so after a year of trade, a lot of cattle have been accumulated. With enough cattle, Ouyang Xuan and Tang Shun discussed and decided to vaccinate the Perak Army on a large scale.

Another important aspect of preventive medicine is the development and production of disinfectants. Although Ouyang Xuan is a chemical engineering professional, it is unrealistic to produce iodine-containing, chlorine-containing and alcohol-containing disinfectants on a large scale under the current production conditions. On the one hand, the industrial production conditions are not up to standard, and on the other hand, the cost is too expensive to use in a large area. Therefore, Ouyang Xuan and Tang Shun discussed, on the one hand, continue to improve the production process of disinfectants, and wait for the raw materials to be sufficient before production. On the other hand, traditional disinfection methods are used, such as burning with fire and scalding with boiling water. Plant ash leaching solution is also a good disinfectant, of course, the most used is quicklime and the disinfectant made of it, which is sufficient and cheap.