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Background With the promotion of national control programs on parasitic and tropical diseases in China, the National Institute of Parasitic Diseases (NIPD), Chinese Center for Disease Control and Prevention has gained significant experience in the global health arena through international cooperation over the last seven decades allowing a multilateral impact in the elimination of major endemic diseases. Methods The achievements of NIPD since 1950 has been analyzed with emphasis on the various stages that started with research and control of the endemic parasitic and other tropical diseases at the national level and progressed via international cooperation into a global presence. Results The major achievements contributed by NIPD consist of (i) improving technical capability; (ii) promoting control and elimination of parasitic and tropical diseases; (iii) participating in global health governance and cooperation; and (iv) developing a cooperation model for technical assistance and global public health development. It is expected that NIPD’s experience of international cooperation will be essential for the dissemination of China's successful experience in global health governance, emergency response and development, with focus on malaria and neglected tropical diseases such as schistosomiasis, soil-borne and food-borne helminthiases and echinococcosis. Conclusions NIPD’s new tasks will not only continue to promote national control of endemic parasitic infections and disease elimination programs in China, but also play a leading role in global health and disease elimination programs in the future.

To ascertain the trends and burden of malaria in China and the costs of interventions for 2011-2015.We analysed the spatiotemporal and demographic features of locally transmitted and imported malaria cases using disaggregated surveillance data on malaria from 2011 to 2015, covering the range of dominant malaria vectors in China. The total and mean costs for malaria elimination were calculated by funding sources, interventions and population at risk.A total of 17 745 malaria cases, including 123 deaths (0.7%), were reported in mainland China, with 15 840 (89%) being imported cases, mainly from Africa and south-east Asia. Almost all counties of China (2855/2858) had achieved their elimination goals by 2015, and locally transmitted cases dropped from 1469 cases in 2011 to 43 cases in 2015, mainly occurring in the regions bordering Myanmar whereThe locally transmitted malaria burden in China has decreased. The key challenge is to address the remaining local transmission, as well as to reduce imported cases from Africa and south-east Asia. Continued efforts and appropriate levels of investment are needed in the 2016-2020 period to achieve elimination.Déterminer l'évolution et la charge du paludisme en Chine ainsi que les coûts des interventions visant son élimination, pour la période de 2011 à 2015.Nous avons analysé les caractéristiques spatio-temporelles et démographiques des cas de transmission locale et d'importation du paludisme, en utilisant des données de surveillance désagrégées sur le paludisme couvrant les principaux vecteurs en Chine sur la période de 2011 à 2015. Les coûts totaux et moyens des efforts d'élimination du paludisme ont été calculés pour chaque source de financement, chaque type d'intervention et en fonction de la population exposée.Un total de 17 745 cas de paludisme, dont 123 mortels (0,7%), a été recensé en Chine continentale, avec 15 840 cas importés (89%), essentiellement depuis l'Afrique et l'Asie du Sud-Est. Pratiquement tous les comtés de Chine (2855/2858) ont atteint leurs objectifs vers l’élimination du paludisme en 2015, et les cas de transmission locale ont chuté de 1469 cas en 2011 à 43 cas en 2015, survenus principalement dans les régions bordant le Myanmar, où les espècesLa charge des cas de transmission locale du paludisme en Chine a diminué. Le principal défi consiste désormais à lutter contre la transmission locale résiduelle et à réduire les cas importés depuis l'Afrique et l'Asie du Sud-Est. Des efforts continus et des niveaux d'investissement appropriés sont nécessaires sur la période 2016-2020 pour atteindre l'objectif d'élimination du paludisme.Determinar las tendencias y la carga de paludismo en China y los costes de las intervenciones entre 2011 y 2015.Se analizaron las características espacio-temporales y demográficas de los casos de paludismo importado y transmitido localmente utilizando datos de seguimiento desglosados sobre el paludismo entre 2011 y 2015, y se cubrió la gama de vectores del paludismo dominantes en China. Se calcularon los costes totales y medios para la eliminación del paludismo teniendo en cuenta las fuentes de financiación, las intervenciones y la población en riesgo.En China continental se registró un total de 17 745 casos de paludismo, incluyendo 123 muertes (0,7%), de los cuales 15 840 (89%) fueron casos importados, principalmente de África y el sudeste asiático. Casi todos los condados de China (2 855/2 858) habían logrado sus objetivos de eliminación para 2015, y los casos transmitidos localmente descendieron de 1 469 casos en 2011 a 43 casos en 2015, principalmente en las regiones fronterizas con Myanmar, dondeLa carga de paludismo transmitido localmente en China ha disminuido. El reto principal es poner remedio a los casos transmitidos localmente que quedan, además de reducir los casos de importación de la infección desde África y el sudeste asiático. Durante el periodo 2016-2020, se necesitan esfuerzos continuos y niveles de inversión adecuados para lograr su eliminación.الغرض الوقوف على الاتجاهات السائدة وأعباء الملاريا في الصين وتكاليف التدخلات للفترة ما بين عامي 2011 و2015. الطريقة حللنا السمات المكانية والزمانية والديمغرافية لحالات الملاريا المنقولة محليًا والواردة باستخدام بيانات مراقبة مفصلة عن الملاريا في الفترة ما بين عامي 2011 و2015، والتي تغطي مجموعة ناقلات الملاريا السائدة في الصين. وقد تم حساب التكاليف الإجمالية والمتوسطة للتخلص من الملاريا على أساس مصادر التمويل والتدخلات والقطاعات السكانية المعرضة للخطر. النتائج وقد تم الإبلاغ عن وجود 17,745 حالة من حالات الملاريا، بما في ذلك 123 حالة وفاة (0.7‏%)، في البر الرئيسي للصين، مع وجود 15,840 حالة واردة (89‏%)، معظمها من أفريقيا وجنوب شرق آسيا. حققت جميع مقاطعات الصين تقريبًا (2855/2858) أهداف القضاء عليها بحلول عام 2015، وانخفضت الحالات المنقولة محليًا من 1469 حالة في عام 2011 إلى 43 حالة في عام 2015، والتي ظهرت أساسًا في المناطق المتاخمة لميانمار حيث تكون كلاً من الأنوفيلة الصغيرة والأنوفيلة الفظيعة كأنواع مسيطرة ناقلة للأمراض. وتم إنفاق ما يصل إلى 134.6 مليون دولار أمريكي في إطار الجهود المبذولة للقضاء على الملاريا خلال الفترة ما بين عامي 2011 و2015، حيث تم الحصول على 57.2 مليون دولار أمريكي (43‏%) من الصندوق العالمي لمحاربة الإيدز والسل والملاريا، و77.3 مليون دولار أمريكي (‏57%) من الحكومة المركزية الصينية. وبلغ متوسط الاستثمار السنوي (27 مليون دولار أمريكي) للشخص المعرض للخطر (574 مليون شخص) 0.05 دولار أمريكي (الانحراف المعياري: 0.03). الاستنتاج انخفض عبء الملاريا المنقولة محليًا في الصين. ويتمثل التحدي الرئيسي في معالجة النقل المحلي المتبقي، بالإضافة إلى الحد من الحالات الواردة من أفريقيا وجنوب شرق آسيا. ويلزم بذل جهود متواصلة ومستويات مناسبة من الاستثمار في الفترة ما بين عامي 2016 و2020 لتحقيق القضاء الكامل عليها.旨在明确 2011-2015 年间中国的疟疾流行趋势和压力及其干预措施成本。.我们使用 2011 至 2015 年间的分散型疟疾监测数据(涵盖中国的显性疟疾媒介的范围)分析了本地传播型及输入型疟疾病例的时空特征和人口特征。 消除疟疾的总成本及平均成本按资金来源、干预措施及危险人群数量进行计算。.中国大陆共报告了 17 745 件疟疾病例,其中包括 123 件 (0.7%) 死亡案例,15 840 件 (89%) 输入型病例。输入来源主要为非洲及东南亚。 中国几乎所有区县 (2855/2858) 已在 2015 年实现了其消灭疟疾的目标,本地传播型病例已由 2011 年的 1469 例下降至 2015 年的 43 例,主要发病区位于缅甸边境地带,该地区主要的媒介种类是中国的本地传播型疟疾疫情已经减轻。 应对剩余的本地传播以及减少来自非洲及东南亚地区的输入型病例是主要挑战。 2016-2020 年期间,中国仍需继续努力并进行适当投资以实现消除疟疾的目标。.Выяснить тенденции и нагрузку в отношении малярии в Китае, а также определить расходы на проведение необходимых мероприятий в период 2011–2015 гг.Мы провели анализ пространственно-временных и демографических особенностей случаев местнотрансмиссивной и завезенной малярии с использованием дезагрегированных данных эпиднадзора за малярией в период с 2011 по 2015 год, охватывающих диапазон доминирующих векторов малярии в Китае. Общие и средние затраты на ликвидацию малярии рассчитывались с учетом источников финансирования, необходимых мероприятий и групп населения, подверженных риску.Всего в континентальном Китае было зарегистрировано 17 745 случаев малярии, в том числе 123 случая со смертельным исходом (0,7%), из которых 15 840 случаев (89%) были завезены, главным образом из Африки и Юго-Восточной Азии. Почти все уезды Китая (2855 из 2858) достигли своих целей по ликвидации заболевания к 2015 году, а число местнотрансмиссивных случаев сократилось с 1469 случаев в 2011 году до 43 случаев в 2015 году, главным образом в регионах, граничащих с Мьянмой, гдеМестнотрансмиссивное бремя малярии в Китае снизилось. Основная задача состоит в том, чтобы решить сохраняющуюся проблему местной передачи инфекции, а также сократить случаи завоза инфекции из Африки и Юго-Восточной Азии. Для завершения ликвидации в 2016–2020 гг. необходимы дальнейшие усилия и соответствующие уровни инвестиций.

As the only specialized institution for research and control of parasitic diseases at the national level in China for almost 70 years, the National Institute of Parasitic Diseases (NIPD) at the Chinese Center for Disease Control and Prevention (China CDC) has been instrumental in supporting the remarkable progress from high prevalence to transmission interruption or low endemicity of several diseases, lymphatic filariasis, malaria and schistosomiasis in particular. This has taken place through technical guidance, emergency response and scientific research as well as providing technical service, education, training, health promotion and international cooperation. With China's increasing involvement in international cooperation and the increased risk for (re)emerging tropical diseases in mind, the Chinese Government designated in 2017 a new Chinese Center for Tropical Disease Research to NIPD. Responding to the expanded responsibilities, the institute is scaling up its activities in several ways: from parasitic diseases to the wider area of tropical diseases; from disease control to disease elimination; from biological research to policy evidences accumulation; and from public health to global health. Based on this new vision and China's previous accomplishments in the areas mentioned, the institute is in a position to move forward with respect to global health and equitable development according to the central principles of the United Nations' Sustainable Development Goals.

The objective of this study was to investigate malaria prevalence after the 2014 earthquakes in Ludian, Yongshan, and Jinggu counties, Yunnan Province, China. We collected and analyzed epidemiological data and made a risk assessment of transmission probability. From January 2005 to July 2015, 87 malaria cases were reported in the three counties, most of which (81.6%) occurred between 2005 and 2009, with five cases reported in Jinggu County between January 2014 and July 2015, of which one case was reported after the earthquake. In addition, no local transmission occurred in the three counties from 2010, and 95.5% of imported malaria occurred in patients who had returned from Myanmar. The townships of Lehong, Qingsheng, and Weiyuan were the main endemic areas in the three counties. The probability of malaria transmission in the three counties was low, but Jinggu County had a higher risk due to the existence of infected patients and an appropriate vector. With sporadic cases reported annually, close monitoring should continue to enhance early detection of a possible malaria outbreak.

To determine the key interventions transferring from the control to elimination of malaria in China so as to provide the basic information for achieving malaria elimination.Based on the data collected from the document entitled of The National Annual Report on Schistosomiasis, Malaria and Echinococcosis, published by the National Institute of Parasitic Diseases of Chinese Center for Disease Control and Prevention, the malaria incidence and intervention data were selected only in the typical endemic provinces during the period of 2004-2010. The correlation between the incidence and interventions in the target provinces was analyzed based on the Panel Data Regression Model, and the key interventions were determined.Four provinces namely Anhui, Yunnan, Hainan and Henan were targeted with 87.56% of the national malaria figures from 2004 to 2010. When Y was given as vivax malaria incidence, X1 as the log of the number of historical cases receiving radical treatment in the pre-transmission stage (RTPT) (F = 14.53, P0.01, R2 = 0.72), X2 as the log of risk population receiving RTPR (F = 15.90, P0.01, R2 = 0.71) and X3 as the number of technicians trained in microscopy (F = 11.53, P0.01, R2 = 0.61), three space-fixed effect models were established respectively, and X1, X2, as well as X3 had negative effects on Y value. When Y was given as falciparum malaria incidence, X1 as the accumulated technicians trained in microscopy (F = 11.06, P0.01, R2 = 0.87), X2 as the log of technicians trained in entomology (F = 15.28, P0.01, R2 = 0.89) , two two-way (space and time) fixed effect models were established respectively, and both X1 and X2 had negative effects on Y value.RTPT among historical patients and at-risk populations as well as microscopy training influences the variation of vivax malaria incidence, while the significant interventions of microscopy training and vector control training indicate that the integrated measures with strengthened capacity in diagnosis and vector control are of importance in the control of falciparum malaria transmission.

To understand the current status of the malaria control programme at the county level in accordance with the criteria of the World Health Organisation, the gaps and feasibility of malaria elimination at the county and national levels were analysed based on three kinds of indicators: transmission capacity, capacity of the professional team, and the intensity of intervention. Finally, a roadmap for national malaria elimination in the People's Republic of China is proposed based on the results of a feasibility assessment at the national level.

The historical patterns of malaria transmission in the People's Republic of China from 1949 to 2010 are presented in this chapter to illustrate the changes in epidemiological features and malaria burden during five decades. A significant reduction of malaria incidence has resulted in initiation of a national malaria elimination programme. However, challenges in malaria elimination have been identified. Foci (or hot spots) have occurred in unstable transmission areas, indicating an urgent need for strengthened surveillance and response in the transition stage from control to elimination.

The Global Fund to Fight AIDS, Tuberculosis and Malaria (GFATM) supported a project on the control and elimination of malaria in People's Republic of China which was one of the biggest-scale international cooperation programmes to control malaria in the country during the past 10 years. The project promoted the effective implementation of the Chinese national malaria control programme. On the basis of epidemiologic data, an overview of the project activities and key performance indicators, the overall impact of the GFATM project was evaluated. We also reviewed relevant programme features including technological and management approaches, with a focus on best practice, innovations in implementation and the introduction of international standards. Last, we summarised the multi-stakeholder cooperation mechanism and comments on its sustainability in the post-GFATM period. Recommendations for the future management of the Chinese national malaria elimination programme are put forward after considering the challenges, shortcomings and lessons learnt during the implementation of the GFATM project in China to sustain past achievements and foster the attainment of the ultimate goal of malaria elimination for the country.

Introduction: This study aimed to investigate the baseline level of malaria awareness in residents in 20 malaria-endemic provinces from October 2010 to January 2011 at the beginning of the implementation of the China National Malaria Elimination Programme (NMEP). Methodology: A structured questionnaire about basic malaria knowledge was administrated to residents in rural areas from 20 provinces, municipalities, and autonomous regions. Results: A total of 182,085 residents no younger than 15 years of age took part in the cross-sectional investigation; 3,232 were excluded because of incomplete survey responses. Of the respondents, 56.86% were aware of malaria, 18.03% responded correctly to all five questions, and 5.57% answered all the questions incorrectly. Malaria awareness among different age groups was statistically significant (p < 0.001), males had a better understanding of malaria than did females (p < 0.001), and Type I counties had a better understanding than did Type II counties (p < 0.001). Conclusions: The level of malaria awareness was low among residents at the beginning of the NMEP, especially about malaria pathogenicity and preventive methods. Health education campaigns should be developed and implemented to increase the public perceptions about malaria prevention and treatment, and to promote malaria elimination in China.

Malaria has affected human health globally with a significant burden of disease, and also has impeded social and economic development in the areas where it is present. In Africa, many countries have faced serious challenges in controlling malaria, in part due to major limitations in public health systems and primary health care infrastructure. Although China is a developing country, a set of control strategies and measures in different local settings have been implemented successfully by the National Malaria Control Programme over the last 60 years, with a low cost of investment. It is expected that Chinese experience may benefit malaria control in Africa. This review will address the importance and possibility of China-Africa collaboration in control of malaria in targeted African countries, as well as how to proceed toward the goal of elimination where this is technically feasible.

The Global Fund to Fight AIDS, Tuberculosis and Malaria (GFATM) supported a project on the control and elimination of malaria in People’s Republic of China which was one of the biggest-scale international cooperation programmes to control malaria in the country during the past 10 years. The project promoted the effective implementation of the Chinese national malaria control programme. On the basis of epidemiologic data, an overview of the project activities and key performance indicators, the overall impact of the GFATM project was evaluated. We also reviewed relevant programme features including technological and management approaches, with a focus on best practice, innovations in implementation and the introduction of international standards. Last, we summarised the multi-stakeholder cooperation mechanism and comments on its sustainability in the post-GFATM period. Recommendations for the future management of the Chinese national malaria elimination programme are put forward after considering the challenges, shortcomings and lessons learnt during the implementation of the GFATM project in China to sustain past achievements and foster the attainment of the ultimate goal of malaria elimination for the country.

The historical patterns of malaria transmission in the People’s Republic of China from 1949 to 2010 are presented in this chapter to illustrate the changes in epidemiological features and malaria burden during five decades. A significant reduction of malaria incidence has resulted in initiation of a national malaria elimination programme. However, challenges in malaria elimination have been identified. Foci (or hot spots) have occurred in unstable transmission areas, indicating an urgent need for strengthened surveillance and response in the transition stage from control to elimination.

To understand the current status of the malaria control programme at the county level in accordance with the criteria of the World Health Organisation, the gaps and feasibility of malaria elimination at the county and national levels were analysed based on three kinds of indicators: transmission capacity, capacity of the professional team, and the intensity of intervention. Finally, a roadmap for national malaria elimination in the People's Republic of China is proposed based on the results of a feasibility assessment at the national level.

Background Insecticide resistance in malaria vectors is a growing concern in many countries and requires immediate attention because of the limited chemical arsenal available for vector control. There is lack of systematic and standard monitoring data of malaria vector resistance in the endemic areas, which is essential for the ambitious goal of malaria elimination programme of China. Methods In 2010, eight provinces from different malaria endemic region were selected for study areas. Bioassays were performed on F1 progeny of Anopheles sinensis reared from wild-caught females using the standard WHO susceptibility test with diagnostic concentrations of 0.25% deltamethrin and 4% DDT. Results For An. sinensis, the results indicated that exposure to 0.25% deltamethrin of F1 families with mortalities ranging from 5.96% to 64.54% and less than 80% mortality to DDT at the diagnostic concentration of 4% across the study areas. Conclusions Anopheles sinensis was completely resistant to both deltamethrin and DDT, and resistance to pyrethroid has risen strikingly compared to that recorded during 1990s. The results highlight the importance of longitudinal insecticide resistance monitoring and the urgent need for a better understanding of the status of insecticide resistance in this region.

To observe the impact on the transmission of schistosomiasis in areas where the local inhabitants migrated from outside embankment to new settlements.Two villages (Chenqiao and Qingjie) where the inhabitants had moved out and another 2 villages (Jiangzhou and Xiaohuang) disused for both inhabitants and cultivated land were selected for the investigation. Data on prevalence in human and domestic animals, and Oncomelania snail habitats, were collected.After moving from outside embankment to new settlements, the density of infested snails in Chenqiao and Qingjie decreased by 79.1% and 45.2% in 2005 compared with that in 2002, and the infection rate of snails decreased by 75.5% and 84.9%, respectively (P001). In Jiangzhou and Xiauhuang, the density of infested snails decreased by 100% and 74.9% in 2005 compared with that in 2002, and the infection rate of snails decreased by 100% and 40.0%, respectively (P0.05). In villages that only disused for inhabitants, the density and egg-positive rate of feces collected from the wild were higher than the other 2 villages. However, in villages disused for both inhabitants and cultivated land, the density and egg-positive rate of wild feces decreased gradually and no egg-positive feces was found in 2005. The prevalence of schistosomiasis in humans in villages disused only for inhabitants changed slightly from 2002 to 2005, but decreased gradually in villages disused for both inhabitants and cultivated land. Higher prevalence in cattle was found in villages disused only for inhabitants. Number of cattle reduced yearly and no cattle left in villages disused for both inhabitants and cultivated land in 2005.No significant change on the factors of schistosomiasis transmission has been found in villages disused only for inhabitants, but the transmission has been effectively controlled in villages disused for both inhabitants and cultivated land.

To study the current situation and the cause of schistosomiasis resurgence in order to provide reference for formulation of control strategy.Data in 1999 - 2003 and baseline data in some areas were collected and analyzed retrospectively.Resurgence was seen in 6.15% (16/260) of the areas and one farm where transmission of schistosomiasis had been interrupted and 33.33% (21/64) of the areas already under control. Snails appeared to have been rebounded only in six counties (farm) while in thirty two counties that rebound was seen in both snails and disease prevalence. Tendency of increase in the total numbers of patients, acute patients and cattle with schistosomiasis, areas with snails were seen from 1999 to 2003.Environmental, ecological, societal factors such as flood, acequia, lack of expenditure and lack of incentives at work etc. contributed to the resurgence of epidemics in those areas that criteria had been reached. Surveillance and supervision on the sources of infection and snail diffusion, especially in the areas where the transmission of schistosomiasis had already been under control.

To understand the risk factors of schistosomiasis transmission in the Three Gorges Reservoir Area (TGRA) and to provide evidence for the development of control strategy.Approaches including epidemiology, immunology and field survey were applied to investigate the potential risk factors which would involve the importation of infectious resources live mobile and migrant population, and livestock in the reservoir area. Meanwhile, observation on survival and reproductive status of snail under simulation habitats was also carried out, using ecological methods on snails. Strategy in preventing the spread of snail as infectious resources was also provided.175 mobile people from schistosomaisis endemic area of were tested and one person showed immunology tests positive with indirect hemagglutination test (IHA) and circumoral precipitin test (COPT), with a positive rate of 0.57%. Through the two-year period under observation, data showed that the snails with ribbon/smooth shells could survive and reproduce under habitats of simulation.Once the infectious resource of schistosomiasis was introduced into the TGRA, the area became a new schistosomiasis epidemic area in TGRA which called for countermeasures to be taken.

To analyze the change of tendency on schistosomiasis epidemics in China in the last 5 years.Data on schistosomiasis epidemics in the history and particularly in the last 5 years were collected. Tendency and the re-emerging status after 1998 were analyzed.Data in 2003 showed that in 42%, 40% and 53% of the provinces, counties and townships with epidemics, the transmission of the disease has been interrupted or controlled. The number of estimated patients of schistosomiasis and areas with snails were also reduced by 92.74% and 73.56%, in 2003. The annual estimated number of chronic cases was around 800 000 and 31 321.5 hectare of snail infested areas were newly identified in recent 5 years. Among 20 national villages under longitudinal surveillance, 30%, 70% and 35% of the villages were presented a tendency of increase in the rates of human infection, bovine infection and Oncomelania snails infection, respectively. A total of 38 counties from 7 provinces have re-emerged in schistosomiasis transmission after those counties having reached criteria of transmission under control or interrupted. In 6 non-endemic counties, snails were presented, and 16 marshlands in Xan river were found with appearance of acute cases of schistosomiasis. More snail infested areas were found in Shanghai, Zhejiang, and Fujian. Both snail infested areas and newly infected cases were occurred in urban areas along the Yangtze River.The tendency of increase was presented in focal areas along the Yangtze River, due to changes of environmental, ecological, societal and economic status, as well as on the forces of control.

Background In the battle against malaria in China, the rate of elementary and high school students’ awareness on malaria knowledge is an important index for malaria elimination, but only rare data is available. This study aimed to investigate the level of malaria awareness in students at elementary and high schools in malaria endemic areas of China, and to provide the baseline information for the malaria elimination. Methods This cross-sectional survey was conducted in 20 different malaria-endemic provinces in the first year of China’s National Malaria Elimination Programme (NMEP). A structured questionnaire was administrated to students at elementary and high schools enrolled. A total of 44,519 questionnaires were effective while 1,220 were excluded because of incomplete survey responses. Results More than 60% of students were aware of malaria, but only 9,013 of them answered correctly to all five questions, and there were still 1,862 students unaware of malaria. There were significant differences of the awareness of malaria among different age groups, between male and female, between two different education levels. Discussion The study reveals that students at elementary and high school levels did not have adequate knowledge of malaria about biology, pathogenicity, transmitting vectors and preventive methods and so on at the beginning of NMEP in China. Further emphasis should be paid on health education campaigns in China to increase students’ public awareness of malaria about vector control, treatment, prevention.