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.

Cost comparison of rapid questionnaire screening for individuals at risk of clonorchiasis in low- and high-prevalence communities in northern Vietnam.

Clonorchiasis is an emerging food-borne trematode infection in Vietnam. Due to the absence of cost-effective preventive measures its control largely relies on morbidity reduction by chemotherapy with praziquantel. We performed a comparative cost estimation of three different diagnostic and intervention approaches in areas of high and low prevalence of clonorchiasis in northern Vietnam in order to select more cost-effective chemotherapy. Our study confirmed that a questionnaire investigating the habit of eating raw, freshwater fish was a rapid, cost-effective and operationally feasible tool for identifying individuals at risk of clonorchiasis in both high-prevalence and low-prevalence areas. The cost of diagnosis and intervention per person and per true positive case was 20-fold higher in low-prevalence areas, regardless of the type of approach. Geographical mapping of high-risk areas prior to screening is, therefore, recommended to maximize the cost-effectiveness of the intervention activities.

Large-scale preventive chemotherapy for the control of helminth infection in Western Pacific countries: six years later.

In 2001, Urbani and Palmer published a review of the epidemiological situation of helminthiases in the countries of the Western Pacific Region of the World Health Organization indicating the control needs in the region. Six years after this inspiring article, large-scale preventive chemotherapy for the control of helminthiasis has scaled up dramatically in the region. This paper analyzes the most recent published and unpublished country information on large-scale preventive chemotherapy and summarizes the progress made since 2000. Almost 39 million treatments were provided in 2006 in the region for the control of helminthiasis: nearly 14 million for the control of lymphatic filariasis, more than 22 million for the control of soil-transmitted helminthiasis, and over 2 million for the control of schistosomiasis. In general, control of these helminthiases is progressing well in the Mekong countries and Pacific Islands. In China, despite harboring the majority of the helminth infections of the region, the control activities have not reached the level of coverage of countries with much more limited financial resources. The control of food-borne trematodes is still limited, but pilot activities have been initiated in China, Lao People's Democratic Republic, and Vietnam.

Cost containment in a school deworming programme targeting over 2.7 million children in Vietnam.

Vietnam is one of the countries in the world most affected by soil-transmitted helminthiases. Large areas of the country, such as the Northern Uplands and the North and Central Coast, are reported as having infection rates of 75-85% for Ascaris lumbricoides, 38-40% for Trichuris trichiura and 27-28% for hookworm infections. Periodical deworming of schoolchildren is therefore strongly recommended. Managers of the Helminth Control Programme decided to apply a number of measures to improve cost efficiency in order to deworm as many schoolchildren as possible with the limited financial resources available. This low-cost intervention targeted over 2.7 million schoolchildren. Coverage was estimated at over 95% and the cost for each treated child was US$ 0.03, which represents a saving of approximately 50% of costs presently reported in the literature. This article describes the measures applied that resulted in cost containment but maintained high treatment coverage.

Evaluation of coverage of deworming interventions in Vietnam.

In 2004-2005, the school deworming program in Vietnam targeted 2,400,000 school-children in 25 provinces. A questionnaire survey of a random sample of schools throughout the country was organized to validate the teacher feedback, assess the real coverage of the program and estimate the occurrence of side-effects. A total of 91 schools in four different provinces were visited few days after drug distribution. A total of 2,323 children and 80 teachers were questioned. The total cost of the monitoring has been estimated at US dollar 7,000 (less than 10% of the deworming program). The survey demonstrated a coverage of 95% for school-children and of 86.3% for teachers (on average a coverage 2% lower than the one reported by the teachers through forms on the day of drug administration). Approximately 0.4% of those interviewed reported side-effects after deworming, while the occurrence of side effects through routine reports was 0.15%. In both cases, the side effects were described as mild forms of nausea, abdominal pain, or headaches that did no required pharmacological treatment. The survey confirmed the positive results of routine reporting; we consider the survey a cost-effective activity to maintain the control activities under monitoring.

Appreciation of school deworming program by parents in Ha Giang Province (Vietnam).

School-based deworming programs are one of the most cost-effective public health strategies to reach children with anthelminthics and health education. However, despite their low cost and high health impact, they are not implemented on a large scale. The present survey investigated a school-based deworming program in Ha Giang Province, Vietnam, to assess the community perception and support towards these programs. Information from 81 households, 88 primary school students, 25 teachers and 9 people in charge of commune health stations was collected by structured questionnaires. The survey displayed complete satisfaction and a high level of support within all 4 questioned groups. In addition 96.1% of all parents noticed an improvement in their children's health. The great appreciation of the deworming program by the community is an additional argument to convince decision makers to implement and scale up these programs. Even teachers that did not receive any specific training were able to distribute the drug successfully following the page of written instructions accompanying the drug.