61 research outputs found
Malaria elimination in Lao PDR: the challenges associated with population mobility
Abstract Although the Lao People’s Democratic Republic (Lao PDR) is comparatively small landlocked country with patterns of both in- and out-migration, its human migration situation has been poorly studied. This is despite all of the country’s 18 provinces sharing both official and unofficial border checkpoints with neighboring countries. Economic reforms in the last decade have seen a gradual increase in the promotion of foreign investment, and main towns and transportation networks have been expanding thus offering new opportunities for livelihoods and economic activities. In the last decade, there has also been a significant reduction of reported malaria cases in Lao PDR and while this is an important prerequisite for eliminating malaria in the country, malaria outbreaks reported in the last four years suggest that population mobility, particularly in the south, is an important factor challenging current control efforts. Bolder investment in social sector spending should be geared towards improving health service provision and utilization, ensuring equitable access to primary health care (including malaria) through efforts to achieve universal health coverage targets. This should be extended to populations that are mobile and migrants. The local government plays a critical role in supporting policy and enforcement issues related to private sector project development in the provinces. Cross-border initiatives with neighboring countries, especially in terms of data sharing, surveillance, and response, is essential. Mechanisms to engage the private sector, especially the informal private sector, needs to be explored within the context of existing regulations and laws. Existing and new interventions for outdoor transmission of malaria, especially in forest settings, for high-risk groups including short- and long-term forest workers and their families, mobile and migrant populations, as well as the military must be combined into integrated packages with innovative delivery mechanisms through social marketing approaches. This should happen at multiple points in the mobility pathway and involve the private sector rather than being fully reliant on the national malaria vertical program This article based on the review of existing literature from abstracts and full texts, includes published, peer-reviewed English language literature sourced through PubMed and grey literature sources through Google and Google Scholar. The review included also case reports, sector reports, conference proceedings, research reports, epidemiology studies, qualitative studies, and census reports in both Lao and English languages. The authors used the search terms: malaria and mobile populations, malaria control program and elimination, health system performance, malaria outbreak, Lao PDR; and included articles published until June 2015
Malar J
BackgroundMalaria morbidity and mortality have been significantly reduced through the proper use of insecticide-treated mosquito nets, but the extra protection afforded by the insecticide diminishes over time. The insecticide depletion rates vary according to location where wash frequency and wear are influenced by cultural habits as well as the availability of water. Monitoring of available insecticides on the net surface is essential for determining the effective life of the net. Therefore, a rapid and inexpensive colorimetric field test for cyanopyrethroids (Cyanopyrethroid Field Test or CFT) was used to measure surface levels of deltamethrin on insecticide-coated polyester nets (PowerNets\ue2\u201e\ua2) in rural Lao PDR over a two-year period.MethodsNet surface levels of deltamethrin were measured by wiping the net with filter paper and measuring the adsorbed deltamethrin using the CFT. A relationship between surface levels of deltamethrin and whole net levels was established by comparing results of the CFT with whole levels assayed by high-performance liquid chromatography (HPLC). An effective deltamethrin surface concentration (EC80) was determined by comparing mosquito mortality (WHO Cone Test) with CFT and HPLC results. Five positions (roof to bottom) on each of 23 matched nets were assayed for deltamethrin surface levels at 6, 12, and 24\ue2\u20ac\u2030months. Mosquito mortality assays (WHO Cone Tests) were performed on a subset of eleven 24-month old nets and compared with the proportion of failed nets as predicted by the CFT.ResultsAt six months, the nets retained about 80% of the baseline (new net) levels of deltamethrin with no significant differences between net positions. At 12\ue2\u20ac\u2030months, ~15-40%, and at 24\ue2\u20ac\u2030months <10% of deltamethrin was retained on the nets, with significant differences appearing between positions. Results from the CFT show that 93% of the nets failed (deltamethrin surface levels </= EC80) at 24\ue2\u20ac\u2030months. This value is in agreement with 91% failure as determined by the WHO Cone Test on a subset of 11 nets. The CFT results show that 50% of the nets from Laos failed at 12\ue2\u20ac\u2030months of normal use.ConclusionThe CFT is a useful and accurate indicator of net efficacy and may be substituted for mosquito bioassays
Deforestation inhibits malaria transmission in Lao PDR: a spatial epidemiology using Earth observation satellites
Abstract Background The present study aimed to analyze the impact of deforestation on the malaria distribution in the Lao People’s Democratic Republic (Lao PDR), with consideration of climate change. Methods Malaria distribution data from 2002 to 2015 were obtained from the Ministry of Health of Lao PDR and each indicator was calculated. Earth observation satellite data (forested area, land surface temperature, and precipitation) were obtained from the Japan Aerospace Exploration Agency (JAXA). Structured equation modeling (SEM) was conducted to clarify the relationship between the malaria incidence and Earth observation satellite data. Results As a result, SEM identified two factors that were independently associated with the malaria incidence: area and proportion of forest. Specifically, malaria was found to be more prevalent in the southern region, with the malaria incidence increasing as the percentage of forested land increased (both p < 0.01). With global warming steadily progressing, forested areas are expected to play an important role in the incidence of malaria in Lao PDR. This is believed because malaria in Lao PDR is mainly forest malaria transmitted by Anopheles dirus. Conclusion To accelerate the elimination of malaria in Lao PDR, it is important to identify, prevent, and intervene in places with increased forest coverage (e.g., plantations) and in low-temperature areas adjacent to malaria-endemic areas, where the vegetation is similar to that in malaria-endemic areas
Characterizing mobility patterns of forest goers in southern Lao PDR using GPS loggers
BACKGROUND: In the Greater Mekong Subregion (GMS), forest-going populations are considered high-risk populations for malaria and are increasingly targeted by national control programmes’ elimination efforts. A better understanding of forest-going populations’ mobility patterns and risk associated with specific types of forest-going trips is necessary for countries in the GMS to achieve their objective of eliminating malaria by 2030. METHODS: Between March and November 2018, as part of a focal test and treat intervention (FTAT), 2,904 forest-goers were recruited in southern Lao PDR. A subset of forest-goers carried an “i-Got-U” GPS logger for roughly 2 months, configured to collect GPS coordinates every 15 to 30 min. The utilization distribution (UD) surface around each GPS trajectory was used to extract trips to the forest and forest-fringes. Trips with shared mobility characteristics in terms of duration, timing and forest penetration were identified by a hierarchical clustering algorithm. Then, clusters of trips with increased exposure to dominant malaria vectors in the region were further classified as high-risk. Finally, gradient boosting trees were used to assess which of the forest-goers’ socio-demographic and behavioural characteristics best predicted their likelihood to engage in such high-risk trips. RESULTS: A total of 122 forest-goers accepted carrying a GPS logger resulting in the collection of 803 trips to the forest or forest-fringes. Six clusters of trips emerged, helping to classify 385 (48%) trips with increased exposure to malaria vectors based on high forest penetration and whether the trip happened overnight. Age, outdoor sleeping structures and number of children were the best predictors of forest-goers’ probability of engaging in high-risk trips. The probability of engaging in high-risk trips was high (~ 33%) in all strata of the forest-going population. CONCLUSION: This study characterized the heterogeneity within the mobility patterns of forest-goers and attempted to further segment their role in malaria transmission in southern Lao People’s Democratic Republic (PDR). National control programmes across the region can leverage these results to tailor their interventions and messaging to high-risk populations and accelerate malaria elimination. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12936-023-04468-8
High heterogeneity in <it>Plasmodium falciparum </it>risk illustrates the need for detailed mapping to guide resource allocation: a new malaria risk map of the Lao People's Democratic Republic
Abstract Background Accurate information on the geographical distribution of malaria is important for efficient resource allocation. The Lao People's Democratic Republic has experienced a major decline in malaria morbidity and mortality in the past decade. However, efforts to respond effectively to these changes have been impeded by lack of detailed data on malaria distribution. In 2008, a countrywide survey on Plasmodium falciparum diagnosed in health centres and villages was initiated to develop a detailed P. falciparum risk map with the aim to identify priority areas for malaria control, estimate population at risk, and guide resource allocation in the Lao People's Democratic Republic. Methods P. falciparum incidence data were collected from point-referenced villages and health centres for the period 2006-2008 during a country-wide survey between December 2008 and January 2009. Using the highest recorded annual rate, continuous surfaces of P. falciparum incidence were produced by the inverse distance weighted interpolation technique. Results Incidence rates were obtained from 3,876 villages and 685 health centres. The risk map shows that P. falciparum is highly heterogeneous in the northern and central regions of the country with large areas of no transmission. In the southern part, transmission is pervasive and the risk of P. falciparum is high. It was estimated that 3.4 million people (60% of the population) live at risk of malaria. Conclusions This paper presents the first comprehensive malaria risk map of the Lao People's Democratic Republic based entirely on empirical data. The estimated population at risk is substantially lower than previous estimates, reflecting the presence of vast areas with focal or no malaria transmission as identified in this study. These findings provide important guidance for malaria control interventions in the Lao People's Democratic Republic, and underline the need for detailed data on malaria to accurately predict risk in countries with heterogeneous transmission.</p
MOESM3 of Prevalence and risk factors for asymptomatic malaria and genotyping of glucose 6-phosphate (G6PD) deficiencies in a vivax-predominant setting, Lao PDR: implications for sub-national elimination goals
Additional file 3. Multivariable Firth penalized-likelihood logistic model for PCR-based malaria parasite positivity (all species), Northern Lao PDR (N= 5,082)
Patients’ adherence to artemisinin-based combination therapy and healthcare workers’ perception and practice in Savannakhet province, Lao PDR
Abstract Background Artemisinin resistance in Plasmodium falciparum has been spreading across Southeast Asia. Patients’ adherence to artemisinin-based combination therapy (ACT) is critical to avoid expanding this resistance. The objectives of this research were to examine patients’ adherence to ACT for the treatment of uncomplicated malaria and to examine the healthcare workers’ perception of medication adherence and their dispensing practices for malaria patients in Savannakhet province, Lao PDR. Methods A prospective observational study of patients and a descriptive study of healthcare workers were conducted in Xepon, Phin, and Nong districts. In the patient study, patients aged 18 years old or older who were prescribed artemether-lumefantrine (AL) at six healthcare facilities between October 2016 and August 2017 were examined. Patient interviews and tablet counts were conducted on the first day of treatment (day 0) and the follow-up day (around day 3). In the healthcare workers study, a self-administered questionnaire survey was conducted. Results Of the 54 patients examined, 51 (94.4%) were adherent to the AL regimen. The other three patients stopped medication because they felt better, even though the importance of completing the regimen was explained to all patients when it was prescribed. Among 152 healthcare workers who had ever instructed a malaria patient, 74.3% reported that they occasionally saw a malaria patient who adhered poorly to medication instructions. The healthcare workers perceived the major reasons for poor adherence to be illiteracy and poor understanding of medication instructions by patients. In practice, 27.6% of the healthcare workers did not regularly explain the importance of completing the regimen to patients, and 32.2% did not often or always confirm the patients’ understanding of medication instructions. Conclusions Patient adherence to AL was high. The healthcare workers perceived that poor adherence was attributable to the patients, i.e., their poor understanding and illiteracy, which appeared to be related to linguistic differences. However, poor adherence also appeared to be attributable to the healthcare workers, who should tell patients of the importance of completing the AL regimen regardless of their improvement in physical condition and also confirm the patients’ understanding of the instructions
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