Abstract: As the scale and volume of China-African cooperation continue to expand, the opportunities inherent in China-African public health cooperation are also on the rise. Malaria prevention and control is one of the primary domains of China-African public health cooperation. Especially after China's elimination of malaria, incorporating China's experience into the local context to accelerate the control and elimination of malaria in Africa, is a critical scientific problem. This article retrospectively analyses the historical China-African cooperative projects on malaria prevention and control such as the artemisinin compound project for rapid clearance of malaria, the China-UK-Tanzania pilot project, and the institution-based network of China-Africa cooperation on malaria elimination (INCAM), cooperation with the World Health Organization, and the contribution of domestic non-governmental organizations. The article also examines the challenges faced in the China-African cooperation for controlling and eliminating malaria and envisions future cooperation directions.

Objective　To analyze the characteristics of the malaria epidemic and the indicators for "1-3-7" from 2021 to 2023 in China, understand the effectiveness and challenges in preventing re-establishment malaria in China, propose response strategies, and provide references for consolidating the achievements of malaria elimination. Methods　The individual malaria case data and focus data from 2021 to 2023 in the "Information System for Infectious Disease Surveillance" and the "Information System for Parasitic Diseases Prevention and Control" were collected, and epidemiological characteristics and indicators for “1-3-7” were analyzed. Results　From 2021 to 2023, a total of 4 132 malaria cases were reported in 31 provinces and Xinjiang Production and Construction Corps, with mainly falciparum malaria (59.2%, 2 445/4 132). The national malaria epidemic reached a historical low of 799 cases in 2021, before rebounding significantly to 2 488 cases in 2023. The top five provinces for malaria cases were Yunnan, Guangdong, Henan, Sichuan, and Shandong, accounting for 49.4% of the total (2 043/4 132) cases. Except for two long incubation cases infected with P. malariae and one non-mosquito-transmitted case, the remaining cases were imported from abroad, mainly from African countries (81.7%, 3 374/4 129), with P. vivax malaria mainly coming from Myanmar (63.7%, 638/1 001). Malaria cases mainly occur in middle-aged men and migrant overseas workers. 142 severe cases and 21 deaths of malaria were reported. 81.8% (3 378/4 132) of malaria cases sought medical attention within 3 days of symptom onset, and the initial diagnosis institutions were mainly county-level, municipal, and provincial hospitals(77.2%), with an accuracy malaria diagnosis rate of above 80.0%. The completion rates of the malaria indicators for "1-3-7" were all above 90.0%. Conclusions　Since the malaria elimination in China, there has been no re-establishment of malaria, and the surveillance response capability has been maintained at a high level. However, the epidemic of imported malaria continued to rise, severely endangering public health in China, especially in areas such as the China-Myanmar border where the risk of re-establishment was high. Currently, it is necessary to further enhance the awareness of the key populations about timely medical consultation for malaria, as well as healthcare workers' vigilance, diagnostic capabilities, and awareness of timely referrals. Efforts should be maintained to investigate and manage epidemics, strengthen prevention and control in key areas such as the China-Myanmar border in Yunnan, and continuously consolidate elimination achievements.

Objective To establish a high-throughput method that can simultaneously, quickly, and accurately detect main malaria-transmitting Anopheles species and their resistance genes in China, providing a high-throughput monitoring tool for monitoring the main malaria vectors in China after malaria elimination. Methods In different sampling locations, including Tengchong City, Yunnan Province; Wenchang City, Hainan Province; and Donggang City, Liaoning Province, adult specimens of mosquitoes, including Anopheles sinensis, Anopheles minimus, Anopheles dirus, and Anopheles anthropophagus, were collected. Polymerase chain reaction (PCR) technology and Sanger sequencing were employed to detect the ITS2, kdr (L1014), rdl (A296), and ace-1 (G119) genes in individual mosquitoes. For the analysis of mixed samples, an optimized multiplex PCR reaction system, custom-designed dual barcode primers, and next-generation sequencing (NGS) technology were utilized to detect the aforementioned genes. The consistency was assessed using Kappa consistency tests and Chi-square tests for multiple rates. Sensitivity, specificity, and the Youden index were calculated using a four-grid table calculation method. The costs associated with each step of the normal operational process for each method were statistically summarized, and the optimal quantity of mixed samples for detection was determined by a comprehensive approach. Results Conventional PCR amplification of gDNA from 300 mosquitoes resulted in 144 individuals of Anopheles sinensis, 53 individuals of Anopheles dirus, 62 individuals of Anopheles anthropophagus, and 41 individuals of Anopheles minimus, as identified by Sanger sequencing. The mutation frequencies of resistance genes kdr (L1014), rdl (A296), and ace-1 (G119) were found in 73, 27, and 41 specimens, respectively. Using a newly established multiplex PCR reaction system based on custom dual barcode and NGS sequencing technology, samples corresponding to Sanger sequencing were detected under different sample sizes. The two methods showed high consistency in the results (all Kappa>0.900). Multiple comparison tests showed significant differences in the consistencies of the two methods across different sample sizes N (40, 80, 160), N (120, 200, 240, 280), and N (300) (χ2=26.547, P<0.001). The new method demonstrated high sensitivity and specificity across various sample sizes, with the Youden index ranging from highest to lowest as follows: 1 (40, 80, 160)>0.994 (120)>0.990 (280)>0.988 (200)>0.987 (240)>0.985 (300). With an increase in sample size from 40 to 300, the cost per sequencing site for the new method decreased from 20.0 yuan to 8.3 yuan, while the cost per sequencing site for the conventional method decreased from 16.7 yuan to 15.4 yuan. The optimal mixed sample size for the new method was determined to be 280. Conclusion The newly developed multiplex PCR and barcode NGS detection method enables simultaneous screening of four major malaria vector mosquito species and the presence of mutations in the ace-1, kdr, and rdl resistance genes, exhibiting excellent stability, high sensitivity, and specificity. It allows for the efficient analysis of large sample sizes in a single run, offering a cost-effective alternative compared to other types of detection methods.

Objective To analyze the epidemiological characteristics of the imported malaria cases in 20 counties at the bor?der region of Yunnan Province from 2012 to 2014,so as to provide the evidence?based proof for adjusting the strategies in the elimination stage. Methods The malaria epidemic data of the 20 border counties in Yunnan Province from 2012 to 2014 were collected and analyzed by using Microsoft Excel 2010. Results From 2012 to 2014,a total of 1 558 malaria cases were report?ed in the 20 border counties in Yunnan Province,among which,1 336 were imported cases,accounting for 85.75%(1 336/1 558),and 222 were indigenous cases,accounting for 14.25%(222/1 558). The number of the imported cases in the above years took up 80.00%(544/680),89.10%(425/477)and 91.52%(367/401)of the total reported cases in the whole year,re?spectively. Among all the 1 336 imported cases,1 045(78.22%)were infected with Plasmodium vivax,284(21.26%)were in?fected with P. falciparum,3 were infected with P. malariae,3 were mixed infection and 1 was an unclassified case;2 patients died. And 95.58%of the cases were mainly infected in Myanmar(1 277 cases). Young and middle?aged adult of 20-40 years who worked overseas were the predominant(802 cases,60.03%)and most of the cases occurred from April to June of the year (679 cases,50.82%). Those cases mainly distributed in Tengchong(459 cases),Ruili(366 cases),Yingjiang(191 cases)and Mangshi(78 cases). Conclusions The epidemic situation of imported malaria is serious in the border region of Yunnan Prov?ince. Therefore,the surveillance system of malaria control needs to be well planned and managed to ensure timely case detection and prompt response at the elimination and post?elimination stage.

Objective To assess the risk of secondary transmission induced by imported malaria in Jiangxi Province，so as to provide the evidence for adjustment of malaria surveillance strategies in the key groups and areas. Methods The Delphi method was used to establish the secondary transmission risk indicator system and the weight of each index was obtained. The data of malaria prevalence，vector distribution and intervention capacity were collected in 100 counties of Jiangxi Province from 2012 to 2015. The transmission potential index（TPI），intervention capacity index（ICI），and malaria risk index（MRI）were calculated for each county. The risk map was drawn with GIS software. Results The top ten counties with highly potential risk indicators were Linchuan District（2.131），Xinzhou District（1.609），Jiujiang County（1.404），Zhanggong District（1.365）， Fengcheng City（1.225），Qingshanhu District（1.184），Yudu County（1.171），Dingnan County（1.018），Xunyang District（1.015）and Zhushan District（1.006）. The high risk areas were mainly distributed in the regions of the capitals of their prefectures and in counties with more floating population. Conclusions There are the risk of the secondary transmission induced by imported malaria in Jiangxi Province. The high risk of the secondary transmission is shown in the areas with more floating population and weaker intervention capacity.

Objective 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. Methods 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 se?lected only in the typical endemic provinces during the period of 2004-2010. The correlation between the incidence and interven?tions in the target provinces was analyzed based on the Panel Data Regression Model,and the key interventions were deter?mined. Results 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,P<0.01,R2=0.72),X2 as the log of risk population receiv?ing RTPR(F=15.90,P<0.01,R2=0.71)and X3 as the number of technicians trained in microscopy(F=11.53,P<0.01,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,P<0.01,R2=0.87),X2 as the log of technicians trained in entomology(F=15.28,P<0.01,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. Conclusion RTPT among historical patients and at?risk populations as well as microscopy training influences the variation of vivax malaria inci? dence,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.

Objective: To analyze the performance of the 5 Global Fund Malaria Programmes in China from 2003 to 2013. Methods: All of the proposals, summaries, progress reports, survey reports, Monitoring& Evaluation reports, and performance rating reports of the 5 Global Fund Malaria Programmes in China and the epidemic data of program areas were collected for statistical analysis from 2012 to 2014. Symposiums were held with relevant experts from national and provincial Centers for Disease Control and Prevention, program managers and staffs from national and provincial Global Fund Malaria Programme offices. The completion of the relevant programme indicators (including the general grant information such as program areas, beneficiaries and funding; the implementation of malaria control measures; the performance of malaria control measures; the malaria incidence in the program areas; the prevalence of malaria parasites; and program management and performance evaluation) were analyzed, and the results: of the symposiums were summarized. Results The implementation period of the 5 Global Fund Malaria Programs were as follows: Round 1 from 2003 to 2008, Round 5 from 2006 to 2010, Round 6 from 2007 to 2012, Round 10 from 2012 to 2013, and National Strategy Application (NSA) from 2010 to 2012. Under the support of all the Global Fund Malaria Programs, a total of 11 936 726 fever cases received microscopic tests, 1 485 915 confirmed and suspected malaria cases were treated, 1 579 773 Long Lasting Insecticide-treated Nets were distributed, 3 414 633 regular nets were treated by insecticide, 40 298 284 primary and middle school students received health education on malaria control. Compared with the baseline value, the completion rates of each indicator increased after the implementation of the programs. The growth value ranged from 12.83% to 83.11%, among which the biggest growth was the value of the indicator'Percentage of households with at least one LLIN/ITN in target areas’, and it increased from 9.2% (baseline value of 2006) to 92.31% (value of 2012). The malaria incidence in program areas has dropped significantly year by year, the annual reported malaria incidence in Yunnan and Hainan provinces decreased from 1 950/100 000, 3 850/100 000 in 2002 to 3.31/100 000, 0.15/100 000 in 2012, the P. falciparum malaria incidence in target counties in Hainan province decreased from 90.6/100 000 in 2002 to 0/100 000 in 2012. As from the implementation of NSA grant in 2010 to 2012, the annual reported malaria incidence in 92% of the 75 Type 1 counties was less than 1 per 10 000, 60.00% of Type 1 counties and 98.69% of the 687 Type 2 counties reported zero locally transmitted malaria cases. The Global Fund Secretariat had conducted a total of 37 performance evaluations, of which 9 have been rated as A1, 4 rated as A2, 19 rated as B1 and 5 rated as B1. Conclusions The Global Fund Malaria Program in China has been closely integrated with the goal and task of National Malaria Control Program, reducing malaria burden in target areas, and pushing Chinese malaria control efforts to move from control to elimination.

With the gradual resumption of international travel, cross-border population movement has become frequent again, risk assessment of imported malaria has important public health significance to maintain malaria elimination status in China. Currently, risk index system construction method, risk index method, mathematical model method, and infectivity-receptivity- vulnerability method are mainly used in imported malaria risk assessment in China. This paper summarizes the common evaluation methods in the risk assessment of imported malaria research in China to provide references for the further research.

There are still multiple challenges in China during the malaria post-elimination phase, including a large number of imported malaria cases with widespread distribution, low awareness of timely healthcare seeking, insufficient malaria diagnosis and treatment capacity of medical institutions and insufficient malaria surveillance and response capability of disease control and prevention institutions. As the core technical institutions for preventing the re-establishment of malaria transmission, both medical institutions and disease control and prevention institutions are required to enhance the collaboration between clinical and public health services, improve the malaria diagnosis and quality management system, intensify case identification and epidemiological investigations, and improve the management mechanism of antimalarial drug reserves. In addition, doctors are encouraged to become the main force in the health education and promotion of malaria prevention to improve the public health literacy. These approaches are recommended to improve the overall capability of timely identification, standardized treatment and effective response of imported malaria cases, so as to continuously consolidate the malaria elimination achievements in China.

Currently, the global malaria epidemic is still severe. China was certified malaria-free by WHO in 2021; however, there is a risk of cross-border importation and secondary transmission of malaria via aircrafts and through land bordering countries in China because of the complex environments in border areas between China and neighboring malaria-endemic countries, notably the explosive growth in the malaria epidemic in Myanmar in China-Myanmar border areas. This article summarizes typical cases of secondary transmission caused by imported malaria across the world, and proposes responses to cross-border importation and secondary transmission of malaria in non-border and border areas of China, in order to effectively reduce the risk of malaria importation and secondary transmission and consolidate the hard earned malaria elimination achievements.