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Fauziah N, Rinawan FR, Nugraha NF, Faridah L, Jati KM, Dakosta A, Santika MK, Zakiyyudin MY, Muhsin A, Rizkillah KF, Nisa MN, Ristandi RB. Malaria elimination in West Java, Indonesia: A descriptive-and-qualitative study. J Vector Borne Dis 2024; 61:183-194. [PMID: 38922652 DOI: 10.4103/jvbd.jvbd_113_23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Accepted: 09/05/2023] [Indexed: 06/27/2024] Open
Abstract
BACKGROUND OBJECTIVES Following World Health Organization (WHO) plans for thirty-five malaria-endemic countries, Indonesia will eliminate malaria by 2030. As one of the Indonesian provinces, West Java targeted subnational malaria elimination in 2022. This article aims to describe malaria surveillance data and elimination programs, including weaknesses in sustaining the program. METHODS This study used secondary data from malaria surveillance information system regencies/cities' case reports for 2019-2022 and achievement data of sub-national malaria elimination certification from each regency/city from 2014-2022. The data was confirmed from the evaluation study document, analysis of reported cases, and interviews. RESULTS Most cases were confirmed by microscopic examination (84.1% in 2021 and 94.4% in 2022) and rapid diagnostic tests (57% in 2019 and 58.1% in 2020). Malaria is more prevalent among men (93% in 2019, 95% in 2020, 96% in 2021, and 95.9% in 2022) and productive ages of 15-64 years (98.8% in 2019, 100% in 2020, 99.2% in 2021, and 98.8% in 2022), frequently occurs in the military (56.3% in 2019, 75.7% in 2020, 45.2% in 2021) and police (40.5% in 2022), often uses passive case detection for identifying cases (97.9% in 2019 and 2020, 95.2% in 2021, and 97.6% in 2022), and the majority undergo inpatient treatment (86.4% in 2019, 81.7% in 2021, and 82.6% in 2022). Most positive cases originated from imported cases, and last indigenous cases were still found in 2019. Plasmodium vivax dominated malaria cases and and relapses were high (55.0% in 2020, and 47.3% in 2022). INTERPRETATION CONCLUSION All regencies/cities have obtained sub-national malaria elimination certification in 2022. West Java has the potential to be verified for Java-Bali sub-national malaria elimination targeted in 2023, albeit cases of imported malaria still occur. It is imperative to address the issue of imported cases transitioning into locally transmitted cases (introduced) by effective coordination across all regencies/cities and inter-provincial efforts.
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Affiliation(s)
- Nisa Fauziah
- Division of Parasitology, Department of Biomedical Sciences, Faculty of Medicine, Universitas Padjadjaran, West Java, Indonesia
- Laboratory of Parasitology, Faculty of Medicine, Universitas Padjadjaran, West Java, Indonesia
- Research Center for Care and Control of Infectious Disease, Universitas Padjadjaran, West Java, Indonesia
| | - Fedri Ruluwedrata Rinawan
- Department of Public Health, Faculty of Medicine, Universitas Padjadjaran, West Java, Indonesia
- Center for Health System Study and Health Workforce Education Innovation, Faculty of Medicine, Universitas Padjadjaran, West Java, Indonesia
- Indonesian Society for Remote Sensing Branch West Java, Indoenesia
| | - Naufal Fakhri Nugraha
- Research Center for Care and Control of Infectious Disease, Universitas Padjadjaran, West Java, Indonesia
| | - Lia Faridah
- Division of Parasitology, Department of Biomedical Sciences, Faculty of Medicine, Universitas Padjadjaran, West Java, Indonesia
- Laboratory of Parasitology, Faculty of Medicine, Universitas Padjadjaran, West Java, Indonesia
- Research Center for Care and Control of Infectious Disease, Universitas Padjadjaran, West Java, Indonesia
| | - Karomahul Malaya Jati
- Undergraduate Medical Study Program, Faculty of Medicine, Universitas Padjadjaran, West Java, Indonesia
| | - Angelina Dakosta
- Undergraduate Medical Study Program, Faculty of Medicine, Universitas Padjadjaran, West Java, Indonesia
| | - Mahatyanta Kalya Santika
- Undergraduate Medical Study Program, Faculty of Medicine, Universitas Padjadjaran, West Java, Indonesia
| | - Muhammad Yusuf Zakiyyudin
- Undergraduate Medical Study Program, Faculty of Medicine, Universitas Padjadjaran, West Java, Indonesia
| | - Ahmad Muhsin
- Undergraduate Medical Study Program, Faculty of Medicine, Universitas Padjadjaran, West Java, Indonesia
| | | | - Miftahul Nurun Nisa
- Health Polytechnic of Health Ministry Yogyakarta, Yogyakarta, Indonesia
- World Health Organization (WHO) Country Office of Indonesia, Jakarta, Indonesia
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Manzoni G, Try R, Guintran JO, Christiansen-Jucht C, Jacoby E, Sovannaroth S, Zhang Z, Banouvong V, Shortus MS, Reyburn R, Chanthavisouk C, Linn NYY, Thapa B, Khine SK, Sudathip P, Gopinath D, Thieu NQ, Ngon MS, Cong DT, Hui L, Kelley J, Valecha NNK, Bustos MD, Rasmussen C, Tuseo L. Progress towards malaria elimination in the Greater Mekong Subregion: perspectives from the World Health Organization. Malar J 2024; 23:64. [PMID: 38429807 PMCID: PMC10908136 DOI: 10.1186/s12936-024-04851-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Accepted: 01/11/2024] [Indexed: 03/03/2024] Open
Abstract
Malaria remains a global health challenge, disproportionately affecting vulnerable communities. Despite substantial progress, the emergence of anti-malarial drug resistance poses a constant threat. The Greater Mekong Subregion (GMS), which includes Cambodia, China's Yunnan province, Lao People's Democratic Republic, Myanmar, Thailand, and Viet Nam has been the epicentre for the emergence of resistance to successive generations of anti-malarial therapies. From the perspective of the World Health Organization (WHO), this article considers the collaborative efforts in the GMS, to contain Plasmodium falciparum artemisinin partial resistance and multi-drug resistance and to advance malaria elimination. The emergence of artemisinin partial resistance in the GMS necessitated urgent action and regional collaboration resulting in the Strategy for Malaria Elimination in the Greater Mekong Subregion (2015-2030), advocating for accelerated malaria elimination interventions tailored to country needs, co-ordinated and supported by the WHO Mekong malaria elimination programme. The strategy has delivered substantial reductions in malaria across all GMS countries, with a 77% reduction in malaria cases and a 97% reduction in malaria deaths across the GMS between 2012 and 2022. Notably, China was certified malaria-free by WHO in 2021. Countries' ownership and accountability have been pivotal, with each GMS country outlining its priorities in strategic and annual work plans. The development of strong networks for anti-malarial drug resistance surveillance and epidemiological surveillance was essential. Harmonization of policies and guidelines enhanced collaboration, ensuring that activities were driven by evidence. Challenges persist, particularly in Myanmar, where security concerns have limited recent progress, though an intensification and acceleration plan aims to regain momentum. Barriers to implementation can slow progress and continuing innovation is needed. Accessing mobile and migrant populations is key to addressing remaining transmission foci, requiring effective cross-border collaboration. In conclusion, the GMS has made significant progress towards malaria elimination, particularly in the east where several countries are close to P. falciparum elimination. New and persisting challenges require sustained efforts and continued close collaboration. The GMS countries have repeatedly risen to every obstacle presented, and now is the time to re-double efforts and achieve the 2030 goal of malaria elimination for the region.
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Affiliation(s)
- Giulia Manzoni
- WHO Mekong Malaria Elimination Programme, Phnom Penh, Cambodia.
- Independent Consultant, Antananarivo, Madagascar.
| | - Rady Try
- WHO Mekong Malaria Elimination Programme, Phnom Penh, Cambodia
| | - Jean Olivier Guintran
- World Health Organization Country Office, Phnom Penh, Cambodia
- Independent Consultant, Le Bar sur Loup, France
| | | | - Elodie Jacoby
- WHO Mekong Malaria Elimination Programme, Phnom Penh, Cambodia
- Independent Consultant, Ho Chi Minh, Viet Nam
| | - Siv Sovannaroth
- National Center for Parasitology, Entomology and Malaria Control, Phnom Penh, Cambodia
| | - Zaixing Zhang
- World Health Organization Country Office, Phnom Penh, Cambodia
| | | | | | - Rita Reyburn
- World Health Organization Country Office, Vientiane, Lao PDR
| | | | - Nay Yi Yi Linn
- National Malaria Control Programme, Nay Pyi Taw, Myanmar
| | - Badri Thapa
- World Health Organization Country Office, Yangon, Myanmar
| | | | - Prayuth Sudathip
- Division of Vector Borne Diseases, Department of Disease Control, Bangkok, Thailand
| | - Deyer Gopinath
- World Health Organization Country Office, Bangkok, Thailand
| | - Nguyen Quang Thieu
- National Institute of Malariology, Parasitology and Entomology, Hanoi, Viet Nam
| | | | | | - Liu Hui
- Yunnan Institute of Parasitic Diseases, Yunnan, China
| | - James Kelley
- World Health Organization, Regional Office for the Western Pacific, Manila, Philippines
| | | | - Maria Dorina Bustos
- World Health Organization, Regional Office for South-East Asia, New Delhi, India
| | | | - Luciano Tuseo
- WHO Mekong Malaria Elimination Programme, Phnom Penh, Cambodia
- World Health Organization, Regional Office for the Western Pacific, Manila, Philippines
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An Q, Li Y, Sun Z, Gao X, Wang H. Seasonal prediction of the distribution of three major malaria vectors in China: Based on an ecological niche model. PLoS Negl Trop Dis 2024; 18:e0011884. [PMID: 38236812 PMCID: PMC10796015 DOI: 10.1371/journal.pntd.0011884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Accepted: 12/26/2023] [Indexed: 01/22/2024] Open
Abstract
Against the backdrop of a global malaria epidemic that remains severe, China has eradicated indigenous malaria but still has to be alert to the risk of external importation. Understanding the distribution of vectors can provide an adequate and reliable basis for the development and implementation of vector control strategies. However, with the decline of malaria prevalence in recent years, the capacity of vector monitoring and identification has been greatly weakened. Here we have used new sampling records, climatic data, and topographic data to establish ecological niche models of the three main malaria vectors in China. The model results accurately identified the current habitat suitability areas for the three species of Anopheles and revealed that in addition to precipitation and temperature as important variables affecting the distribution of Anopheles mosquitoes, topographic variables also influenced the distribution of Anopheles mosquitoes. Anopheles sinensis is the most widespread malaria vector in China, with a wide region from the northeast (Heilongjiang Province) to the southwest (Yunnan Province) suitable for its survival. Suitable habitat areas for Anopheles lesteri are concentrated in the central, eastern, and southern regions of China. The suitable habitat areas of Anopheles minimus are the smallest and are only distributed in the border provinces of southern China. On this basis, we further assessed the seasonal variation in habitat suitability areas for these three major malaria vectors in China. The results of this study provide new and more detailed evidence for vector monitoring. In this new era of imported malaria prevention in China, regular reassessment of the risk of vector transmission is recommended.
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Affiliation(s)
- Qi An
- College of Veterinary Medicine, Northeast Agricultural University, Harbin, People’s Republic of China
- Key Laboratory of the Provincial Education Department of Heilongjiang for Common Animal Disease Prevention and Treatment, College of Veterinary Medicine, Northeast Agricultural University, Harbin, People’s Republic of China
| | - Yuepeng Li
- College of Veterinary Medicine, Northeast Agricultural University, Harbin, People’s Republic of China
- Key Laboratory of the Provincial Education Department of Heilongjiang for Common Animal Disease Prevention and Treatment, College of Veterinary Medicine, Northeast Agricultural University, Harbin, People’s Republic of China
| | - Zhuo Sun
- College of Veterinary Medicine, Northeast Agricultural University, Harbin, People’s Republic of China
- Key Laboratory of the Provincial Education Department of Heilongjiang for Common Animal Disease Prevention and Treatment, College of Veterinary Medicine, Northeast Agricultural University, Harbin, People’s Republic of China
| | - Xiang Gao
- College of Veterinary Medicine, Northeast Agricultural University, Harbin, People’s Republic of China
- Key Laboratory of the Provincial Education Department of Heilongjiang for Common Animal Disease Prevention and Treatment, College of Veterinary Medicine, Northeast Agricultural University, Harbin, People’s Republic of China
| | - Hongbin Wang
- College of Veterinary Medicine, Northeast Agricultural University, Harbin, People’s Republic of China
- Key Laboratory of the Provincial Education Department of Heilongjiang for Common Animal Disease Prevention and Treatment, College of Veterinary Medicine, Northeast Agricultural University, Harbin, People’s Republic of China
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Chen Y, Zhang H, Chen H, Fan L, Xu C, Xu J, Chen S, Chen K, Wei Y. Malaria epidemiological characteristics and control in Guangzhou, China, 1950-2022. Malar J 2023; 22:265. [PMID: 37691114 PMCID: PMC10494454 DOI: 10.1186/s12936-023-04696-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Accepted: 08/31/2023] [Indexed: 09/12/2023] Open
Abstract
BACKGROUND Malaria was once widespread in Guangzhou, China. However, a series of control measures have succeeded in eliminating local malaria infections. Based on the analysis of the characteristics of malaria epidemics in Guangzhou, China, from 1950 to 2022, the changes and effectiveness of malaria control strategies and surveillance management in Guangzhou from 1950 to 2022 are described. METHODS Data on malaria prevention and treatment in Guangzhou from 1950 to 2022 were collected, and descriptive epidemiological methods were used to analyse the prevalence of malaria, preventive and control measures taken, and the effectiveness of prevention and treatment in different periods. Data on malaria cases were obtained from the Guangzhou Centre for Disease Control and Prevention (CDC) and the China Communicable Disease Reporting System. RESULTS The development of the malaria control system in Guangzhou has gone through four periods: 1. High malaria prevalence (1950-1979), 2. Intensive prevention and control stage (1980-2000), 3. Consolidating gains in malaria control (2001-2008), and 4. Preventing reestablishment of transmission (2009-2022). During Period 1, only medical institutions at all levels and the local CDCs, the Guangzhou CDC participated in the malaria prevention and control system, establishing a three-tier health system on malaria prevention and control. During Period 2, other types of organizations, including the agricultural sector, schools and village committees, the construction department and street committee, are involved in the malaria control system. During Period 3, more and more organizations are joining forces to prevent and control malaria. A well-established multisectoral malaria control mechanism and an improved post-elimination surveillance management system are in place. Between 1950 and 2022, a total of 420,670 cases of malaria were reported. During Period 1, there was an epidemic of malaria in the early 1950s, with an annual incidence rate of more than 10,000/100,000, including a high rate of 2887.98/100,000 in 1954. In Period 2 malaria was gradually brought under control, with the average annual malaria incidence rate dropping to 3.14/100,000. During Period 3, the incidence rate was kept below 1/100,000, and by 2009 local malaria infections were eliminated. CONCLUSION For decades, Guangzhou has adopted different malaria control strategies and measures at different epidemic stages. Increased collaboration among civil organizations in Guangzhou in malaria control has led to a significant decline in the number of malaria cases and the elimination of indigenous malaria infections by 2009.The experience of Guangzhou can guide the development of malaria control strategies in other cities experiencing similar malaria epidemics.
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Affiliation(s)
- Yuehua Chen
- Institute of Public Health, Guangzhou Medical University, Guangzhou, China
- Department of Parasite and Endemic Disease Prevention and Control, Guangzhou Center for Disease Control and Prevention, Guangzhou, China
| | - Hao Zhang
- Institute of Public Health, Guangzhou Medical University, Guangzhou, China
- Department of Parasite and Endemic Disease Prevention and Control, Guangzhou Center for Disease Control and Prevention, Guangzhou, China
| | - Haiyan Chen
- Institute of Public Health, Guangzhou Medical University, Guangzhou, China
- Department of Parasite and Endemic Disease Prevention and Control, Guangzhou Center for Disease Control and Prevention, Guangzhou, China
| | - Lirui Fan
- Institute of Public Health, Guangzhou Medical University, Guangzhou, China
- Department of Parasite and Endemic Disease Prevention and Control, Guangzhou Center for Disease Control and Prevention, Guangzhou, China
| | - Conghui Xu
- Institute of Public Health, Guangzhou Medical University, Guangzhou, China
- Department of Parasite and Endemic Disease Prevention and Control, Guangzhou Center for Disease Control and Prevention, Guangzhou, China
| | - Jianmin Xu
- Institute of Public Health, Guangzhou Medical University, Guangzhou, China
- Department of Parasite and Endemic Disease Prevention and Control, Guangzhou Center for Disease Control and Prevention, Guangzhou, China
| | - Shouyi Chen
- Institute of Public Health, Guangzhou Medical University, Guangzhou, China
- Department of Parasite and Endemic Disease Prevention and Control, Guangzhou Center for Disease Control and Prevention, Guangzhou, China
| | - Kuncai Chen
- Institute of Public Health, Guangzhou Medical University, Guangzhou, China
- Department of Parasite and Endemic Disease Prevention and Control, Guangzhou Center for Disease Control and Prevention, Guangzhou, China
| | - Yuehong Wei
- Institute of Public Health, Guangzhou Medical University, Guangzhou, China.
- Department of Parasite and Endemic Disease Prevention and Control, Guangzhou Center for Disease Control and Prevention, Guangzhou, China.
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Lin K, Wang S, Sui Y, Zhang T, Luo F, Shi F, Qian Y, Li J, Lu S, Cotter C, Wang D, Li S. Evaluation of an Innovative Point-of-Care Rapid Diagnostic Test for the Identification of Imported Malaria Parasites in China. Trop Med Infect Dis 2023; 8:296. [PMID: 37368714 DOI: 10.3390/tropicalmed8060296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2023] [Revised: 04/20/2023] [Accepted: 05/25/2023] [Indexed: 06/29/2023] Open
Abstract
BACKGROUND China was certified malaria-free by the World Health Organization on 30 June 2021. However, due to imported malaria, maintaining a malaria-free status in China is an ongoing challenge. There are critical gaps in the detection of imported malaria through the currently available tools, especially for non-falciparum malaria. In the study, a novel point-of-care Rapid Diagnostic Test designed for the detection of imported malaria infections was evaluated in the field. METHODS Suspected imported malaria cases reported from Guangxi and Anhui Provinces of China during 2018-2019 were enrolled to evaluate the novel RDTs. Diagnostic performance of the novel RDTs was evaluated based on its sensitivity, specificity, positive and negative predictive values, and Cohen's kappa coefficient, using polymerase chain reaction as the gold standard. The Additive and absolute Net Reclassification Index were calculated to compare the diagnostic performance between the novel RDTs and Wondfo RDTs (control group). RESULTS A total of 602 samples were tested using the novel RDTs. Compared to the results of PCR, the novel RDTs presented sensitivity, specificity, PPV, NPV, and diagnostic accuracy rates of 78.37%, 95.05%, 94.70%, 79.59%, and 86.21%, respectively. Among the positive samples, the novel RDTs found 87.01%, 71.31%, 81.82%, and 61.54% of P. falciparum, P. ovale, P. vivax, and P. malariae, respectively. The ability to detect non-falciparum malaria did not differ significantly between the novel and Wondfo RDTs (control group). However, Wondfo RDTs can detect more P. falciparum cases than the novel RDTs (96.10% vs. 87.01%, p < 0.001). After the introduction of the novel RDTs, the value of the additive and absolute Net Reclassification Index is 1.83% and 1.33%, respectively. CONCLUSIONS The novel RDTs demonstrated the ability to distinguish P. ovale and P. malariae from P. vivax which may help to improve the malaria post-elimination surveillance tools in China.
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Affiliation(s)
- Kangming Lin
- Guangxi Zhuang Autonomous Region Center for Disease Control and Prevention, Nanning 530028, China
| | - Shuqi Wang
- Anhui Provincial Center for Disease Control and Prevention, Hefei 230601, China
| | - Yuan Sui
- Brown School, Washington University, St. Louis, MO 63130, USA
| | - Tao Zhang
- Anhui Provincial Center for Disease Control and Prevention, Hefei 230601, China
| | - Fei Luo
- Chongqing Center for Disease Control and Prevention, Chongqing 400042, China
| | - Feng Shi
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention (Chinese Center for Tropical Diseases Research), National Health Commission Key Laboratory of Parasite and Vector Biology, WHO Collaborating Center for Tropical Diseases, National Center for International Research on Tropical Diseases, Shanghai 200025, China
| | - Yingjun Qian
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention (Chinese Center for Tropical Diseases Research), National Health Commission Key Laboratory of Parasite and Vector Biology, WHO Collaborating Center for Tropical Diseases, National Center for International Research on Tropical Diseases, Shanghai 200025, China
| | - Jun Li
- Guangxi Zhuang Autonomous Region Center for Disease Control and Prevention, Nanning 530028, China
| | - Shenning Lu
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention (Chinese Center for Tropical Diseases Research), National Health Commission Key Laboratory of Parasite and Vector Biology, WHO Collaborating Center for Tropical Diseases, National Center for International Research on Tropical Diseases, Shanghai 200025, China
| | - Chris Cotter
- Malaria Elimination Initiative, Institute for Global Health Sciences, University of California San Francisco, San Francisco, CA 94109, USA
- Department of Women's and Children's Health, Uppsala University, 75309 Uppsala, Sweden
| | - Duoquan Wang
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention (Chinese Center for Tropical Diseases Research), National Health Commission Key Laboratory of Parasite and Vector Biology, WHO Collaborating Center for Tropical Diseases, National Center for International Research on Tropical Diseases, Shanghai 200025, China
- School of Global Health, Chinese Center for Tropical Diseases Research, Shanghai Jiao Tong University School of Medicine, Shanghai 201100, China
| | - Shizhu Li
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention (Chinese Center for Tropical Diseases Research), National Health Commission Key Laboratory of Parasite and Vector Biology, WHO Collaborating Center for Tropical Diseases, National Center for International Research on Tropical Diseases, Shanghai 200025, China
- School of Global Health, Chinese Center for Tropical Diseases Research, Shanghai Jiao Tong University School of Medicine, Shanghai 201100, China
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Yi B, Zhang L, Yin J, Zhou S, Xia Z. 1-3-7 surveillance and response approach in malaria elimination: China's practice and global adaptions. Malar J 2023; 22:152. [PMID: 37161379 PMCID: PMC10169118 DOI: 10.1186/s12936-023-04580-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Accepted: 04/28/2023] [Indexed: 05/11/2023] Open
Abstract
There has been a significant reduction in malaria morbidity and mortality worldwide from 2000 to 2019. However, the incidence and mortality increased again in 2020 due to the disruption to services during the COVID-19 pandemic. Surveillance to reduce the burden of malaria, eliminate the disease and prevent its retransmission is, therefore, crucial. The 1-3-7 approach proposed by China has played an important role in eliminating malaria, which has been internationally popularized and adopted in some countries to help eliminate malaria. This review summarizes the experience and lessons of 1-3-7 approach in China and its application in other malaria-endemic countries, so as to provide references for its role in eliminating malaria and preventing retransmission. This approach needs to be tailored and adapted according to the region condition, considering the completion, timeliness and limitation of case-based reactive surveillance and response. It is very important to popularize malaria knowledge, train staff, improve the capacity of health centres and monitor high-risk groups to improve the performance in eliminating settings. After all, remaining vigilance in detecting malaria cases and optimizing surveillance and response systems are critical to achieving and sustaining malaria elimination.
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Affiliation(s)
- Boyu Yi
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention (Chinese Center for Tropical Diseases Research), NHC Key Laboratory of Parasite and Vector Biology, WHO Collaborating Center for Tropical Diseases, National Center for International Research on Tropical Diseases, Shanghai, 200025, China
| | - Li Zhang
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention (Chinese Center for Tropical Diseases Research), NHC Key Laboratory of Parasite and Vector Biology, WHO Collaborating Center for Tropical Diseases, National Center for International Research on Tropical Diseases, Shanghai, 200025, China
| | - Jianhai Yin
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention (Chinese Center for Tropical Diseases Research), NHC Key Laboratory of Parasite and Vector Biology, WHO Collaborating Center for Tropical Diseases, National Center for International Research on Tropical Diseases, Shanghai, 200025, China
| | - Shuisen Zhou
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention (Chinese Center for Tropical Diseases Research), NHC Key Laboratory of Parasite and Vector Biology, WHO Collaborating Center for Tropical Diseases, National Center for International Research on Tropical Diseases, Shanghai, 200025, China
| | - Zhigui Xia
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention (Chinese Center for Tropical Diseases Research), NHC Key Laboratory of Parasite and Vector Biology, WHO Collaborating Center for Tropical Diseases, National Center for International Research on Tropical Diseases, Shanghai, 200025, China.
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Liu Y, Zhang T, Chen SB, Cui YB, Wang SQ, Zhang HW, Shen HM, Chen JH. Retrospective analysis of Plasmodium vivax genomes from a pre-elimination China inland population in the 2010s. Front Microbiol 2023; 14:1071689. [PMID: 36846776 PMCID: PMC9948256 DOI: 10.3389/fmicb.2023.1071689] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2022] [Accepted: 01/04/2023] [Indexed: 02/11/2023] Open
Abstract
Introduction In malaria-free countries, imported cases are challenging because interconnections with neighboring countries with higher transmission rates increase the risk of parasite reintroduction. Establishing a genetic database for rapidly identifying malaria importation or reintroduction is crucial in addressing these challenges. This study aimed to examine genomic epidemiology during the pre-elimination stage by retrospectively reporting whole-genome sequence variation of 10 Plasmodium vivax isolates from inland China. Methods The samples were collected during the last few inland outbreaks from 2011 to 2012 when China implemented a malaria control plan. After next-generation sequencing, we completed a genetic analysis of the population, explored the geographic specificity of the samples, and examined clustering of selection pressures. We also scanned genes for signals of positive selection. Results China's inland populations were highly structured compared to the surrounding area, with a single potential ancestor. Additionally, we identified genes under selection and evaluated the selection pressure on drug-resistance genes. In the inland population, positive selection was detected in some critical gene families, including sera, msp3, and vir. Meanwhile, we identified selection signatures in drug resistance, such as ugt, krs1, and crt, and noticed that the ratio of wild-type dhps and dhfr-ts increased after China banned sulfadoxine-pyrimethamine (SP) for decades. Discussion Our data provides an opportunity to investigate the molecular epidemiology of pre-elimination inland malaria populations, which exhibited lower selection pressure on invasion and immune evasion genes than neighbouring areas, but increased drug resistance in low transmission settings. Our results revealed that the inland population was severely fragmented with low relatedness among infections, despite a higher incidence of multiclonal infections, suggesting that superinfection or co-transmission events are rare in low-endemic circumstances. We identified selective signatures of resistance and found that the proportion of susceptible isolates fluctuated in response to the prohibition of specific drugs. This finding is consistent with the alterations in medication strategies during the malaria elimination campaign in inland China. Such findings could provide a genetic basis for future population studies, assessing changes in other pre-elimination countries.
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Affiliation(s)
- Ying Liu
- National Institute of Parasitic Diseases, Chinese Center for Diseases Control and Prevention (Chinese Center for Tropical Diseases Research), Shanghai, China,National Health Commission of the People’s Republic of China (NHC) Key Laboratory of Parasite and Vector Biology, Shanghai, China,World Health Organization (WHO) Collaborating Center for Tropical Diseases, Shanghai, China,National Center for International Research on Tropical Diseases, Shanghai, China,Henan Provincial Center for Disease Control and Prevention, Zhengzhou, China
| | - Tao Zhang
- Anhui Provincial Center for Disease Control and Prevention, Hefei, China
| | - Shen-Bo Chen
- National Institute of Parasitic Diseases, Chinese Center for Diseases Control and Prevention (Chinese Center for Tropical Diseases Research), Shanghai, China,National Health Commission of the People’s Republic of China (NHC) Key Laboratory of Parasite and Vector Biology, Shanghai, China,World Health Organization (WHO) Collaborating Center for Tropical Diseases, Shanghai, China,National Center for International Research on Tropical Diseases, Shanghai, China
| | - Yan-Bing Cui
- National Institute of Parasitic Diseases, Chinese Center for Diseases Control and Prevention (Chinese Center for Tropical Diseases Research), Shanghai, China,National Health Commission of the People’s Republic of China (NHC) Key Laboratory of Parasite and Vector Biology, Shanghai, China,World Health Organization (WHO) Collaborating Center for Tropical Diseases, Shanghai, China,National Center for International Research on Tropical Diseases, Shanghai, China
| | - Shu-Qi Wang
- Anhui Provincial Center for Disease Control and Prevention, Hefei, China
| | - Hong-Wei Zhang
- Henan Provincial Center for Disease Control and Prevention, Zhengzhou, China
| | - Hai-Mo Shen
- National Institute of Parasitic Diseases, Chinese Center for Diseases Control and Prevention (Chinese Center for Tropical Diseases Research), Shanghai, China,National Health Commission of the People’s Republic of China (NHC) Key Laboratory of Parasite and Vector Biology, Shanghai, China,World Health Organization (WHO) Collaborating Center for Tropical Diseases, Shanghai, China,National Center for International Research on Tropical Diseases, Shanghai, China,Hai-Mo Shen, ✉
| | - Jun-Hu Chen
- National Institute of Parasitic Diseases, Chinese Center for Diseases Control and Prevention (Chinese Center for Tropical Diseases Research), Shanghai, China,National Health Commission of the People’s Republic of China (NHC) Key Laboratory of Parasite and Vector Biology, Shanghai, China,World Health Organization (WHO) Collaborating Center for Tropical Diseases, Shanghai, China,National Center for International Research on Tropical Diseases, Shanghai, China,School of Global Health, Chinese Center for Tropical Diseases Research, Shanghai Jiao Tong University School of Medicine, Shanghai, China,*Correspondence: Jun-Hu Chen, ✉
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Survey of malaria vectors on the Cambodia, Thailand and China-Laos Borders. Malar J 2022; 21:399. [PMID: 36585690 PMCID: PMC9801360 DOI: 10.1186/s12936-022-04418-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Accepted: 12/15/2022] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND Anopheles maculatus, Anopheles minimus and Anopheles dirus are the major vectors of malaria transmission in the Greater Mekong Subregion (GMS). The malaria burden in this region has decreased significantly in recent years as all GMS countries progress towards malaria elimination. It is necessary to investigate the Anopheles diversity and abundance status and assess the Plasmodium infection rates to understand the malaria transmission potential of these vector species in GMS countries to guide the development of up-to-date vector control strategies and interventions. METHODS A survey of mosquitoes was conducted in Stung Treng, Sainyabuli and Phongsaly Provinces on the Cambodia-Laos, Thailand-Laos and China-Laos borders, respectively. Mosquito collection was done by overnight trapping at sentinel sites in each province. After morphological identification, the 18S rRNA-based nested-PCR was performed to detect malaria parasites in the captured Anopheles mosquitoes. RESULTS A total of 18 965 mosquitoes comprising of 35 species of 2 subgenera (Subgenus Anopheles and Subgenus Cellia) and 4 tribes (Tribes Culicini, Aedini, Armigerini and Mansoniini) were captured. Tribe Culicini accounted for 85.66% of captures, followed by Subgenus Anopheles (8.15%). Anopheles sinensis dominated the Subgenus Anopheles by 99.81%. Plasmodium-infection was found in 25 out of the 1 683 individual or pooled samples of Anopheles. Among the 25 positive samples, 19, 5 and 1 were collected from Loum, Pangkhom and Siem Pang village, respectively. Eight Anopheles species were found infected with Plasmodium, i.e., An. sinensis, Anopheles kochi, Anopheles vagus, An. minimus, Anopheles annularis, Anopheles philippinensis, Anopheles tessellatus and An. dirus. The infection rates of Plasmodium falciparum, Plasmodium vivax and mixture of Plasmodium parasite species were 0.12% (2/1 683), 1.31% (22/1 683) and 0.06% (1/1 683), respectively. CONCLUSIONS Overall, this survey re-confirmed that multiple Anopheles species carry malaria parasites in the international border areas of the GMS countries. Anopheles sinensis dominated the Anopheles collections and as carriers of malaria parasites, therefore may play a significant role in malaria transmission. More extensive investigations of malaria vectors are required to reveal the detailed vector biology, ecology, behaviour, and genetics in GMS regions in order to assist with the planning and implementation of improved malaria control strategies.
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Zhang T, Wang D, Qian Y, Ruan W, Liu Y, Xia J, Yan H, Sui Y, Lu S, Xu X, Jiang J, Lyu X, Wang S, Li S, Li W. Profile and determinants of delayed care-seeking and diagnosis among patients with imported malaria: a retrospective study in China, 2014-2021. Infect Dis Poverty 2022; 11:125. [PMID: 36550586 PMCID: PMC9773583 DOI: 10.1186/s40249-022-01050-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Accepted: 12/14/2022] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND In areas where malaria has been eliminated, delayed care-seeking and diagnosis of imported malaria are constant threats. This study aimed to describe the profile and determinants of delayed care-seeking and diagnosis among patients with imported malaria in China. METHODS This retrospective study assessed surveillance data obtained from 2014 to 2021 in the Chinese provincial-level administrative divisions (PLADs) of Anhui, Henan, Hubei, and Zhejiang, and Guangxi. Epidemiological characteristics were analyzed using descriptive statistics. Furthermore, factors associated with delayed care-seeking and diagnosis among imported malaria cases were identified using multivariate logistic regression. RESULTS Overall, 11.81% and 30.08% of imported malaria cases had delays in seeking care and diagnosis, respectively. During the study period, there was a decreasing trend in the proportion of imported malaria cases with delayed care-seeking (χ2 = 36.099, P < 0.001) and diagnosis (χ2 = 11.395, P = 0.001). In multivariate analysis, independent risk factors associated with delayed care-seeking include PLADs (Guangxi as reference), consultations in high-level facilities for the first medical visit, infections with non-Plasmodium falciparum species, and older age. However, PLADs (Guangxi as reference), the purpose of traveling (labour as reference), and infections with non-P. falciparum species increased the risk of delayed diagnosis. Delayed care-seeking (adjusted odds ratio: 1.79, P = 0.001) and diagnosis (adjusted odds ratio: 1.62, P = 0.004) were risk factors for severe disease development. CONCLUSIONS Based on this study's findings, we strongly advocate for improved access to quality healthcare to reduce the rate of misdiagnosis at the first visit. Infections caused by non-P. falciparum species should be highlighted, and more sensitive and specific point-of-care detection methods for non-P. falciparum species should be developed and implemented. In addition, education programs should be enhanced to reach target populations at risk of malaria infection. All these factors may reduce delayed care-seeking and diagnosis of imported malaria.
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Affiliation(s)
- Tao Zhang
- grid.410620.10000 0004 1757 8298Anhui Provincial Center for Disease Control and Prevention, Hefei, 230601 China
| | - Duoquan Wang
- grid.508378.1National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention (Chinese Center for Tropical Diseases Research), NHC Key Laboratory of Parasite and Vector Biology, WHO Collaborating Center for Tropical Diseases, National Center for International Research on Tropical Diseases, Shanghai, 200025 China ,grid.16821.3c0000 0004 0368 8293School of Global Health, Chinese Center for Tropical Diseases Research, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025 China
| | - Yingjun Qian
- grid.508378.1National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention (Chinese Center for Tropical Diseases Research), NHC Key Laboratory of Parasite and Vector Biology, WHO Collaborating Center for Tropical Diseases, National Center for International Research on Tropical Diseases, Shanghai, 200025 China
| | - Wei Ruan
- grid.433871.aZhejiang Provincial Center for Disease Control and Prevention, Hangzhou, 310051 China
| | - Ying Liu
- grid.418504.cHenan Provincial Center for Disease Control and Prevention, Zhengzhou, 450016 China
| | - Jing Xia
- grid.508373.a0000 0004 6055 4363Hubei Provincial Center for Disease Control and Prevention, Wuhan, 430079 China
| | - Hui Yan
- grid.418332.fGuangxi Zhuang Autonomous Region Center for Disease Control and Prevention, Nanning, 530028 China
| | - Yuan Sui
- grid.4367.60000 0001 2355 7002Brown School, Washington University, St. Louis, MO USA
| | - Shenning Lu
- grid.508378.1National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention (Chinese Center for Tropical Diseases Research), NHC Key Laboratory of Parasite and Vector Biology, WHO Collaborating Center for Tropical Diseases, National Center for International Research on Tropical Diseases, Shanghai, 200025 China
| | - Xian Xu
- grid.410620.10000 0004 1757 8298Anhui Provincial Center for Disease Control and Prevention, Hefei, 230601 China
| | - Jingjing Jiang
- grid.410620.10000 0004 1757 8298Anhui Provincial Center for Disease Control and Prevention, Hefei, 230601 China
| | - Xiaofeng Lyu
- grid.410620.10000 0004 1757 8298Anhui Provincial Center for Disease Control and Prevention, Hefei, 230601 China
| | - Shuqi Wang
- grid.410620.10000 0004 1757 8298Anhui Provincial Center for Disease Control and Prevention, Hefei, 230601 China
| | - Shizhu Li
- grid.508378.1National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention (Chinese Center for Tropical Diseases Research), NHC Key Laboratory of Parasite and Vector Biology, WHO Collaborating Center for Tropical Diseases, National Center for International Research on Tropical Diseases, Shanghai, 200025 China ,grid.16821.3c0000 0004 0368 8293School of Global Health, Chinese Center for Tropical Diseases Research, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025 China
| | - Weidong Li
- grid.410620.10000 0004 1757 8298Anhui Provincial Center for Disease Control and Prevention, Hefei, 230601 China
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Zhang L, Yi B, Xia Z, Huang F. Plasmodium vivax in the Elimination Phase - China, 2013-2020. China CDC Wkly 2022; 4:609-613. [PMID: 35919476 PMCID: PMC9339366 DOI: 10.46234/ccdcw2022.133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2022] [Accepted: 04/26/2022] [Indexed: 11/14/2022] Open
Abstract
What is already known about this topic? Plasmodium vivax (P. vivax) was the most widely distributed and major human malaria parasite in China, considered the last parasite to be eliminated.
What is added by this report? The last domestic P. vivax case was reported in 2016, while hundreds of imported cases were reported annually from 2013–2020, predominantly from Southeast Asia.
What are the implications for public health practice? In the post-elimination phase, adaptive and practical strategies focusing on imported P. vivax cases should be updated and adopted to prevent malaria resurgence.
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Affiliation(s)
- Li Zhang
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Chinese Center for Tropical Diseases Research, WHO Collaborating Center for Tropical Diseases, National Centre for International Research on Tropical Diseases, NHC Key Laboratory of Parasite and Vector Biology (National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention), Shanghai, China
| | - Boyu Yi
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Chinese Center for Tropical Diseases Research, WHO Collaborating Center for Tropical Diseases, National Centre for International Research on Tropical Diseases, NHC Key Laboratory of Parasite and Vector Biology (National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention), Shanghai, China
| | - Zhigui Xia
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Chinese Center for Tropical Diseases Research, WHO Collaborating Center for Tropical Diseases, National Centre for International Research on Tropical Diseases, NHC Key Laboratory of Parasite and Vector Biology (National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention), Shanghai, China
| | - Fang Huang
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Chinese Center for Tropical Diseases Research, WHO Collaborating Center for Tropical Diseases, National Centre for International Research on Tropical Diseases, NHC Key Laboratory of Parasite and Vector Biology (National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention), Shanghai, China
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Polymorphisms of potential drug resistant molecular markers in Plasmodium vivax from China–Myanmar border during 2008‒2017. Infect Dis Poverty 2022; 11:43. [PMID: 35462549 PMCID: PMC9036727 DOI: 10.1186/s40249-022-00964-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Accepted: 03/21/2022] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
Plasmodium vivax remains the predominant species at the China–Myanmar border, imposing a major challenge to the recent gains in regional malaria elimination. To closely supervise the emerging of drug resistance in this area, we surveyed the variations in genes potentially correlated with drug resistance in P. vivax parasite and the possible drug selection with time.
Methods
A total of 235 P. vivax samples were collected from patients suffering uncomplicated malaria at Yingjiang, Tengchong, and Longling counties, and Nabang port in China, Yunnan province, and Laiza sub-township in Myanmar, from 2008 to 2017. Five potential drug resistance genes were amplified utilizing nested-PCR and analyzed, including pvdhfr, pvdhps, pvmdr1, pvcrt-o, and pvk12. The Pearson’s Chi-squared test or Fisher’s exact test were applied to determine the statistical frequency differences of mutations between categorical data.
Results
The pvdhfr F57I/L, S58R, T61M and S117T/N presented in 40.6%, 56.7%, 40.1%, and 56.0% of the sequenced P. vivax isolates, and these mutations significantly decreased with years. The haplotype formed by these quadruple mutations predominated in Yingjiang, Tengchong, Longling and Nabang. While a mutation H99S/R (56.6%) dominated in Laiza and increased with time. In pvdhps, the A383G prevailed in 69.2% of the samples, which remained the most prevalent haplotype. However, a significant decrease of its occurrence was also noticed over the time. The S382A/C and A553G existed in 8.4% and 30.8% of the isolates, respectively. In pvmdr1, the mutation Y976F occurred at a low frequency in 5/232 (2.2%), while T958M was fixed and F1076L was approaching fixed (72.4%). The K10 insertion was detected at an occurrence of 33.2% in pvcrt-o, whereas there was no significant difference among the sites or over the time. No mutation was identified in pvk12.
Conclusions
Mutations related with resistance to antifolate drugs are prevalent in this area, while their frequencies decrease significantly with time, suggestive of increased susceptibility of P. vivax parasite to antifolate drugs. Resistance to chloroquine (CQ) is possibly emerging. However, since the molecular mechanisms underneath CQ resistance is yet to be better understood, close supervision of clinical drug efficiency and continuous function investigation is urgently needed to alarm drug resistance.
Graphical abstract
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Yin J, Yan H, Li M. Prompt and precise identification of various sources of infection in response to the prevention of malaria re-establishment in China. Infect Dis Poverty 2022; 11:45. [PMID: 35436964 PMCID: PMC9014402 DOI: 10.1186/s40249-022-00968-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Accepted: 04/07/2022] [Indexed: 11/10/2022] Open
Abstract
Prompt and precise diagnosis of patients is an essential component of malaria control and elimination strategies, it is even more vital for the prevention of malaria re-establishment in the post elimination phase. After eliminating malaria in China, the strategy for prevention of malaria re-establishment was updated in a timely manner from the elimination strategy focusing on each case/focus to the prevention of re-establishment focusing on timely identification of the source of infection. However, there are numerous challenges, such as the persistent large number of imported malaria cases, the long-term threat of border malaria, unknown levels of asymptomatic infections and Plasmodium falciparum HRP2/3 gene deletions, and the continuous spreading of antimalarial drug resistance. Meanwhile, the detection capacity also need to be further improved to meet the timely detection of all sources of infection, otherwise it is bound to occur introduced malaria cases and malaria re-establishment in the presence of malaria vector mosquitoes. Therefore, it is necessary to continuously strengthen the malaria detection competency at all levels, promote the research and development on the malaria parasitological testing technologies, thus improving the timely detection of various sources of infection, and preventing the re-establishment of malaria.
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Affiliation(s)
- Jianhai Yin
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention (Chinese Center for Tropical Diseases Research), NHC Key Laboratory of Parasite and Vector Biology, WHO Collaborating Center for Tropical Diseases, National Center for International Research on Tropical Diseases, Shanghai, 200025, China.
| | - He Yan
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention (Chinese Center for Tropical Diseases Research), NHC Key Laboratory of Parasite and Vector Biology, WHO Collaborating Center for Tropical Diseases, National Center for International Research on Tropical Diseases, Shanghai, 200025, China
| | - Mei Li
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention (Chinese Center for Tropical Diseases Research), NHC Key Laboratory of Parasite and Vector Biology, WHO Collaborating Center for Tropical Diseases, National Center for International Research on Tropical Diseases, Shanghai, 200025, China
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