When Feng Lanzhou 65438-0929 entered Peking Union Medical College, he decided to start with vector insects and study and solve common parasitic diseases in China. At that time, there was little research on parasitic diseases in China. From 65438 to the early 1930s, only a few scientists from research institutions in big cities such as Guangzhou, Hangzhou, Shanghai and Peiping made a few preliminary investigations on malaria, leishmaniasis and schistosomiasis, and the research on medical insects was almost blank. There are no senior personnel specializing in medical insects in parasitology major of Peking Union Medical College. Feng Lanzhou collected the adults and larvae of Anopheles mosquitoes in the suburbs of Beiping with his entomological knowledge when he participated in the work of the Royal Society at school, and made detailed morphological observation and identification. The working conditions in rural areas in southern China are very poor. Without the skilled technology of collecting, preserving and identifying insects, it is difficult to obtain complete scientific data. During the period of 1930 ~ 1935, Feng Lanzhou visited Jiangsu, Zhejiang and Jiangxi rural areas many times and collected many specimens, which laid a good foundation for scientific research. He made a detailed investigation on the epidemic factors of falciparum malaria among road workers in Xiamen, and published the article "Study on Malaria and its Infection in Xiamen" at 1932. It is the first time in China that Anopheles minimus is the main vector of malaria by dissecting Anopheles and checking the infection rate of plasmodium according to mosquito spores. 1934 published the survey results of Guangxi 13 county, namely "Malaria and its Transmission in Guangxi". This was a complete and convincing malaria epidemiological report at that time, which further confirmed that Anopheles minimus was an important insect vector in the mountainous areas of southern China. Later, he summarized the distribution of mosquitoes in China according to the results of his investigation and collection of mosquito specimens in southern China and the types of mosquitoes reported in the literature, so as to see the relationship between the distribution of some mosquitoes and diseases. Anopheles minimus as a vector of malaria has been reported in Southeast Asia. Feng Lanzhou's work proved for the first time that Anopheles minimus is also an important malaria vector in China, thus opening the way for malaria control in China.
It is proved that there is Malay filariasis in China, and Anopheles sinensis is an important vector of Malay filariasis.
1878, the British parasitologist patrick manson (1844 ~ 1922) first discovered that Culex pipiens quinquefasciatus is the vector of filariasis bancrofti in Xiamen. At that time, it was not clear whether there was filariasis malayi infection in China. Feng Lanzhou chose Zhejiang as the investigation point of filariasis vector. He also made some technical preparations before working in the field. In Peiping, he used filariasis, which is common in dogs, as experimental materials. He observed the morphology of microfilaria of filariasis canis. He observed the structure of microfilaria more clearly by living staining, and then carried out mosquito transmission experiments to observe the development of filarial larvae at different stages in mosquitoes. From 65438 to 0932, two different forms of microfilaria were found in the blood of local filariasis patients in Huzhou, Zhejiang Province. Feng Lanzhou took the specimen back to Beiping, and compared the structures of two kinds of microfilaria by living staining method, which proved that there are two different kinds of filariasis in China-Bancroftian filariasis and Malayan filariasis. After identifying the local filariasis species, he investigated the natural infection rate of different local mosquito species to filariasis, and determined that Anopheles sinensis was the main vector of filariasis in Malay, Zhejiang. In order to further prove that Anopheles sinensis is a good vector of malaysian filariasis, he also carried out artificial infection tests and made a very detailed morphological description of the development of malaysian filariasis larvae in different periods of Anopheles sinensis. The related articles published by him are the early classic works of filariasis research in China. Work in this field was interrupted by the July 7th Incident.
Study on Leishmania transmitted by sandflies and relapsing fever transmitted by ticks.
In the mid-1965438+1930s, He Wu discovered Leishmania sinensis naturally infected in northern Jiangsu, but whether these naturally infected sandflies can transmit Leishmania sinensis to the final host mammals has not been confirmed by experiments. Whether Kala-azar has intermediate hosts (such as dogs) is also lack of scientific basis in China.
During the period of War of Resistance against Japanese Aggression, Feng Lanzhou studied mass media of Kala-azar in Peiping. He cooperated with Zhong Huilan in 1939. After Li Zongen, he proved that dogs in Peiping can be infected with leishmaniasis. In the same year, they found that China sandfly was naturally infected with Leishmania in Peiping. After China sandfly sucked the blood of kala-azar dogs, Leishmania propagated in sandfly, moved to the front of sandfly and blocked its throat. 194 1 year, they found a sick dog in the home of a kala-azar patient in Cherry Valley behind the reclining Buddha Temple. They kept the sick dog in an empty room. At night, the sick dog attracted a large number of sandflies from China and Mongolia to feed on blood. They caught these bloodsucking sandflies and fed them for dissection, and found that only sandflies in China would be infected. Bite hamsters (an experimental animal sensitive to kala-azar) with these infected sandflies, which will spread kala-azar to hamsters. This is the first time in China that kala-azar has been successfully transmitted to susceptible animals with naturally infected ampelopsis. This shows that sandflies can not only infect but also spread kala-azar. In the experiment, Feng Lanzhou found a strange phenomenon: after China and Mongolia sandflies sucked the blood of kala-azar dogs, Leishmania was found in their stomachs, but only the former could spread kala-azar, while the latter could not. Feng Lanzhou carefully dissected two kinds of sandflies and found that they formed different food envelopes after sucking blood. After the sandfly sucks blood, it forms a complete membrane between the stomach and the inhaled blood, which is located in the gastric mucosa and outside the blood clot, and is called the food outer membrane. The food envelope of the Chinese sandfly is broken shortly after the sandfly sucks blood, and the inhaled Leishmania can drill out of the food envelope, move from the stomach to the pharynx and reproduce in the pharynx. When the sandfly sucks blood again, it will inject pathogens into the new host. However, the food outer membrane of the Mongolian sandfly does not break. But its blood has been wrapped with Leishmania, so that it is finally excreted with feces. Because Leishmania can't move to the pharynx of Mongolian sandfly, Mongolian sandfly can't spread kala-azar. The discovery of this mechanism confirmed that the Chinese sandfly is a good transmission medium of kala-azar, and also showed Feng Lanzhou's meticulous observation and exquisite anatomical techniques.
Before the outbreak of War of Resistance against Japanese Aggression, the spread of relapsing fever was also observed by ticks and ticks in Feng Lanzhou. In the past, there was a saying that spirochetes became invisible granules after 7 hours to 8 days in the stomach of ticks or ticks, and returned to spiral shape after 9 ~ 10 days. After the lice or ticks inhaled the blood containing spirochetes, the two of them directly extracted body fluids from different parts of the lice or ticks and observed them under a dark field microscope, instead of using the conventional section staining method, so they could clearly find spirochetes that were difficult to stain. As a result, they found that the spirochete was sucked into the stomach of ticks or ticks for several hours, then passed through the stomach wall and entered the body cavity, and propagated by binary division. So they denied that the spirochete had an invisible period in his life history. They also pointed out that the spread of relapsing fever is not caused by the feces of lice or ticks, but by the body fluids crushed by lice or the secretions from the basal ganglia of ticks polluting the wounds.
Treatment of taeniasis with areca catechu and pumpkin seeds
Many drugs for treating parasitic diseases are recorded in ancient books in China. From 65438 to 0949, Feng Lanzhou tried betel nut to treat taeniasis, and the effect was very good. During War of Resistance against Japanese Aggression's period, when he was a researcher in the pharmaceutical factory affiliated to Tianjin East Asia Wool Mill, he prepared a compound of betel nut bismuth iodine, and the curative effect was similar to that of betel nut decoction. After the founding of the People's Republic of China, Feng Lanzhou continued to study the curative effect of traditional Chinese medicine on parasitic diseases. When betel nut was used to treat taenia solium in the past, he found that the drug had a good effect of expelling taenia solium, and all 22 cases were cured, but the drug had a poor effect of expelling taenia solium, and only 5 cases were cured in 16 cases. After consulting ancient prescriptions and clinical observation, he proposed to treat taeniasis with betel nut and pumpkin seeds. He used this method to treat taeniasis patients among slaughterhouse workers in Beijing, and found that the curative effect of this method on both taeniasis was above 90%. Both traditional Chinese medicines have the effect of paralyzing tapeworm adults. After the two tapeworms were driven out of the human body, he took out the tapeworms, washed them and put them in normal saline. After the worm resumed its activity, pumpkin seed solution or areca nut solution were added respectively, and the action sites of the two drugs were observed in vitro. The results showed that betel nut could paralyze the front end of Taenia solium and pumpkin seed could paralyze the back end of Taenia solium. Areca catechu can paralyze the front and back of Taenia solium. This proves why the combination of betel nut and pumpkin seeds can effectively repel Taenia solium. This therapy is convenient, economical and effective, and has become a routine method for the treatment of taeniasis in China.
To understand the relationship between Anopheles sinensis with narrow egg type and transmitted diseases
Since the founding of the People's Republic of China, parasitology research in China has developed rapidly. It has been proved that Anopheles minimus is the main vector of malaria transmission in hilly areas of southern China. The mosquito killer has achieved good results in killing Anopheles minimus in Hainan Island. But in the vast plains and hilly areas of central China, what is the main vector of malaria? Is Anopheles sinensis an important vector? These problems have not been solved. Anopheles sinensis is widely distributed in China with a large number. If we blindly destroy all Anopheles sinensis before studying the role of Anopheles sinensis in disease transmission, it will cause unnecessary waste of manpower and material resources. 1938, Yao Yongzheng and others reported at an international conference that the adults of Anopheles sinensis lay three types of eggs. According to his past experience, Feng Lanzhou pointed out through analysis that Anopheles sinensis may not be a pure population, and different types are similar in morphology, but different in living habits and disease transmission. To prove his idea, he went to Guangxi from 1953 to 1954, chose a place where malaria and filariasis were prevalent, and observed the infection rate of Anopheles sinensis with wide eggs and narrow eggs. He found that the infection rate of Anopheles sinensis with narrow egg type was significantly higher than that with wide egg type, which indicated that Anopheles sinensis with narrow egg type was the main vector of Malay filariasis in mountainous and hilly areas. The next year, he made another observation in Hangzhou and reached the same conclusion. Later, he made a comparative study on the specimens of Anopheles sinensis in endemic and non-endemic areas of filariasis and malaria in China. The comparison results showed that Anopheles mosquitoes in filariasis endemic areas were mainly of narrow egg type. 196 1 year, he instructed researchers to observe the morphology of adults, eggs, larvae and pupae of two different egg types of Anopheles sinensis, and made a detailed comparison with other mosquito species in the population of Anopheles sinensis, and finally determined that Anopheles sinensis with narrow egg type was a new subspecies. Later, this subspecies was called Anopheles sinensis subspecies Anopheles anthropophagus, and they made a preliminary analysis of this subspecies' habits. The paper written was not published in time because of the "Cultural Revolution", and when 1975 published the article, Feng Lanzhou had died for three years. These results have been confirmed by the epidemiological investigation of malaria and filariasis in various places, which provides an important scientific basis for vector control of malaria and filariasis in central China.