Malaria: elimination tale from Yunnan Province of China and new challenges for reintroduction

Progress towards malaria elimination in the Greater Mekong Subregion: perspectives from the World Health Organization

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.

Assessing the risk of malaria local transmission and re-introduction in China from pre-elimination to elimination: A systematic review

Assessing the risk of malaria local transmission and re-introduction is crucial for the preparation and implementation of an effective elimination campaign and the prevention of malaria re-introduction in China. Therefore, this review aims to evaluate the risk factors for malaria local transmission and re-introduction in China over the period of pre-elimination to elimination. Data were obtained from six databases searched for studies that assessed malaria local transmission risk before malaria elimination and re-introduction risk after the achievement of malaria elimination in China since the launch of the NMEP in 2010, employing the keywords "malaria" AND ("transmission" OR "re-introduction") and their synonyms. A total of 8,124 articles were screened and 53 articles describing 55 malaria risk assessment models in China from 2010 to 2023, including 40 models assessing malaria local transmission risk (72.7%) and 15 models assessing malaria re-introduction risk (27.3%). Factors incorporated in the 55 models were extracted and classified into six categories, including environmental and meteorological factors (39/55, 70.9%), historical epidemiology (35/55, 63.6%), vectorial factors (32/55, 58.2%), socio-demographic information (15/26, 53.8%), factors related to surveillance and response capacity (18/55, 32.7%), and population migration aspects (13/55, 23.6%). Environmental and meteorological factors as well as vectorial factors were most commonly incorporated in models assessing malaria local transmission risk (29/40, 72.5% and 21/40, 52.5%) and re-introduction risk (10/15, 66.7% and 11/15, 73.3%). Factors related to surveillance and response capacity and population migration were also important in malaria re-introduction risk models (9/15, 60%, and 6/15, 40.0%). A total of 18 models (18/55, 32.7%) reported the modeling performance. Only six models were validated internally and five models were validated externally. Of 53 incorporated studies, 45 studies had a quality assessment score of seven and above. Environmental and meteorological factors as well as vectorial factors play a significant role in malaria local transmission and re-introduction risk assessment. The factors related to surveillance and response capacity and population migration are more important in assessing malaria re-introduction risk. The internal and external validation of the existing models needs to be strengthened in future studies.

1-3-7 surveillance and response approach in malaria elimination: China's practice and global adaptions

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.

Evolution of anti-malaria policies and measures in P.R. China for achieving and sustaining malaria-free

Malaria is a major public health threat worldwide, and it was also widely prevalent in the history in China, seriously endangering people's health and affecting socioeconomic development. China was certified malaria elimination in 2021 with unremitting efforts since the founding of the People's Republic of China in 1949. This great achievement has been another milestone in the fight against major infectious diseases following the elimination of smallpox, poliomyelitis, leprosy, filariasis, neonatal tetanus and blinding trachoma in China. This paper briefly introduces the malaria burden dynamics and the corresponding malaria transmission risk stratificantions, as well as systematically reviews the evolution of anti-malaria policies and measures from severe epidemic to elimination in China. Meanwhile, five key lessons in malaria control and elimination in China are also briefly summarized. All of the above provide evidences for promoting global malaria eradication and preventing reestablishment of malaria transmission, finally benefit all individuals still suffering from the scourge of malaria.

The public health response to an outbreak of border-spill malaria along China-Myanmar border

INTRODUCTION

Malaria importation can be caused by cross-border movement either of both people and anopheline mosquitoes. However, there still lacks robust evidence of imported malaria caused by Plasmodium spp. infected anopheles along international border areas (border-spill malaria). The objectives of this study were to confirm whether an outbreak of Plasmodium vivax malaria is border-spill malaria and assess the effects of China's public health response along China-Myanmar border.

METHODS

Epidemiological, parasitological and entomological investigations were conducted to investigate the outbreak of border-spill malaria. Meanwhile, comprehensive interventions were carried out to prevent further transmission and reintroduction of malaria.

RESULTS

Rapid diagnostic testing, microscopy and polymerase chain reaction were performed and the infections were confirmed as P. vivax. A total of 22 (9.21%) of 239 workers contracted P. vivax during the outbreak. Multivariate logistic regression analysis identified that the distance of worker shelters in China within 300 meters to the internally displaced person (IDP) camps in Myanmar was a risk factors associated with malaria infection (adjusted odds ratio 7.5920; 95% confidence interval, 2.6079-22.1013; P = 0.0002). After comprehensive interventions, malaria transmission was successfully interpreted and prevented at the project site till the completion of project on 14 January 2020, and recurrence of P. vivax malaria was not detected by the end of 2020.

CONCLUSION

This study provided robust evidence of border-spill malaria along China-Myanmar border. Malaria parasite reservoir and distance travelled by female anopheline mosquitoes are two determinants for border-spill malaria. The public health response to the outbreak indicates that the malaria surveillance and response system works well in preventing reintroduction of malaria. However, prevention of border-spill malaria is still a major challenge in the Yunnan border area, China.

Achievements of the national malaria control and elimination program in the People's Republic of China: the Atlas of Malaria Transmission in China

In 2017, China achieved the target of zero indigenous malaria case for the first time, and has been certified as malaria free by World Health Organization in 2021. To further summarize the historical achievements and technical experiences of the elimination program, a project on the Roadmap Analysis and Verification for Malaria Elimination in China was carried out. Results of the project were compiled and published as the Atlas of Malaria Transmission in China (The Atlas). The Atlas using modern digital information technologies, has been supported by various data from 24 malaria endemic provinces of China since 1950, to assess the changes in malaria epidemic patterns from 1950 to 2019 at national and provincial levels. The Atlas is designed as two volumes, including a total of 1850 thematic maps and more than 130 charts, consisting of introductory maps, thematic maps of malaria epidemic and control at national and provincial levels. It objectively and directly shows the epidemic history, evolution process, and great achievements of the national malaria control and elimination program in China. The Atlas has important reference value for summing up historical experience in the national malaria elimination program of China, and malaria control and elimination in other endemic countries in the world.

Lead/Drug Discovery from Natural Resources

Natural products and their derivatives have been shown to be effective drug candidates against various diseases for many years. Over a long period of time, nature has produced an abundant and prosperous source pool for novel therapeutic agents with distinctive structures. Major natural-product-based drugs approved for clinical use include anti-infectives and anticancer agents. This paper will review some natural-product-related potent anticancer, anti-HIV, antibacterial and antimalarial drugs or lead compounds mainly discovered from 2016 to 2022. Structurally typical marine bioactive products are also included. Molecular modeling, machine learning, bioinformatics and other computer-assisted techniques that are very important in narrowing down bioactive core structural scaffolds and helping to design new structures to fight against key disease-associated molecular targets based on available natural products are considered and briefly reviewed.

Science in One Health: A new journal with a new approach

One Health recognizes the close links and interdependence among human health, animal health and environmental health. With the pandemic of COVID-19 and the risk of many emerging or reemerging infectious diseases of zoonotic nature as well as the spreading antimicrobial resistance, One Health has become one of top concerns globally, as it entails the essential global public health challenges from antimicrobial resistance over zoonoses, to climate change, food security and societal well-being. Research priorities in One Health include the study on interactions of human-animal-plants-nature ecology interface, systems thinking, integrated surveillance and response systems, and the overall One Health governance as part of the global health and sustainability governance. The now launched journal, Science in One Health, aims to be a resource platform that disseminates scientific evidence, knowledge, and tools on the One Health approaches and respective possible socio-ecological interventions. Thus, aims at providing fruitful exchanges of information and experience among researchers, and decision makers as well as public health actors.

Application of an innovative grid-based surveillance strategy to ensure elimination and prevent reintroduction of malaria in high-risk border communities in China

Grid management is a grassroots governance strategy widely implemented in China since 2004 to improve the government’s efficiency to actively find and solve problems among populated regions. A grid-based strategy surveillancing high-risk groups, including mobile and migrant populations (MMPs), in the China–Myanmar border region has played an indispensable role in promoting and consolidating the malaria elimination efforts by tracking and timely identification of potential importation or re-establishment of malaria among MMPs. A sequential mixed methods was implementated to explore the operational mechanism and best practices of the grid-based strategy including through the focus group discussions (FGDs), comparison of before and after the implementation of a grid-based strategy in the field sites, and data collection from the local health system.This paper distills the implementation mechanism and highlights the role of the grid-based strategy in the elimination and prevention of re-establishment of malaria transmission.

China's long march to malaria elimination: a case of adaptive management

Since the 1950s, China has transitioned from a malaria pandemic country with tens of millions of annual cases, through phases of local control and elimination, to sustained national malaria elimination efforts. This marks the first time a country in the World Health Organization (WHO) Western Pacific region has been certified malaria-free in more than 3 decades. This article provides an innovative approach to understanding China’s malaria elimination journey. A number of articles and commentaries have analysed the effectiveness of specific technical approaches implemented in China. Our argument is that we need to look beyond these, and consider the ways in which policy development and implementation capacities have been fostered to support the dynamic change management. The article makes a number of arguments. First is the pragmatic adaptiveness of policies and strategies—and implementation capacities. Second, China has invested in building systems as well as capacities to support the elimination of parasitic diseases, including malaria. Third, the country has both benefited from, and contributed to, global health collaboration on malaria elimination. The ongoing work by the authors is identifying a number of key factors.

Historical experiences on mass drug administration for malaria control and elimination, its challenges and China's experience: a narrative review

After decades of efforts, malaria is still a major public health problem in many countries, especially in sub-Saharan Africa. Mass drug administration (MDA) has been one of the interventions used to control malaria. China, the largest and most populous country in the world, has recently achieved malaria elimination with MDA within its strategy. Therefore, knowing the history of the use of MDA, and its advantages and challenges are crucial to better implement MDA as a component of malaria control and elimination strategy. This narrative review focused on the use of MDA from the past to present, the experiences of successful and failed MDA interventions to control malaria in Africa, Asia, and South Pacific region, the challenges faced, as well as China's experience in malaria control and elimination. A direct search using key words and phrases was conducted using the web search engines Google and Google Scholar, peer-reviewed journal websites and PubMed database to mainly screen articles on MDA studies with positive and negative results, the World Health Organization guidelines, and other MDA-related reports. We also summarized our historical field experiences on MDA in malaria control to provide informed perspective on the challenges of MDA. Following the spirit of innovation, a comprehensive strategy with MDA at its core and each additional measure compensating one another's shortage based on different malaria transmission settings and stratification could be the highlight of future malaria control and elimination strategy to help achieve the vision of a malaria-free world.

What sub-Saharan African countries can learn from malaria elimination in China

Malaria is one of the most devastating diseases plaguing the sub-Saharan African region since time immemorial. In spite of a global reduction in mortality rates, a significant proportion of deaths due to malaria is still accounted for in the region. China recently joined the 40 countries declared malaria free by the World Health Organization and became the first country in the WHO Western Pacific Region to be awarded the certification. We commented on the strategies employed by China to eliminate malaria, address challenges facing malaria control in sub-Saharan Africa, and derive lessons that could be learned in the sub-Saharan African context.