Malaria risk stratification in Lao PDR guides program planning in an elimination setting.

Malaria in Lao People's Democratic Republic (Lao PDR) has declined rapidly over the last two decades, from 279,903 to 3926 (99%) cases between 2001 and 2021. Elimination of human malaria is an achievable goal and limited resources need to be targeted at remaining hotspots of transmission. In 2022, the Center of Malariology, Parasitology and Entomology (CMPE) conducted an epidemiological stratification exercise to assign districts and health facility catchment areas (HFCAs) in Lao PDR based on malaria risk. The stratification used reported malaria case numbers from 2019 to 2021, risk maps derived from predictive modelling, and feedback from malaria staff nationwide. Of 148 districts, 14 were deemed as burden reduction (high risk) districts and the remaining 134 as elimination (low risk) districts. Out of 1235 HFCAs, 88 (7%) were classified as highest risk, an improvement from 187 (15%) in the last stratification in 2019. Using the HFCA-level stratification, the updated stratification resulted in the at-risk population (total population in Strata 2, 3 and 4 HFCAs) declining from 3,210,191 to 2,366,068, a 26% decrease. CMPE are using the stratification results to strengthen targeting of resources. Updating national stratifications is a necessary exercise to assess progress in malaria control, reassign interventions to the highest risk populations in the country and ensure greatest impact of limited resources.

Expanding malaria diagnosis and treatment in Lao PDR: lessons learned from a public-private mix initiative.

BACKGROUND: As in other countries of the Greater Mekong Sub-region (GMS), the private health sector constitutes a significant avenue where malaria services are provided and presents a unique opportunity for public-private collaboration. In September 2008, a public-private mix (PPM) strategy was launched initially in four northern and southern provinces in Lao PDR to increase access to rapid diagnostic tests (RDTs) and artemisinin-based combination therapy (ACT), improve quality of care, and collect routine malaria data from the private sector. Throughout the process, key stakeholders were involved in the planning, monitoring and supervision of project sites. Following an initial assessment in 2009, the PPM initiative expanded to an additional 14 district sites to a total of 245 private pharmacies and 16 clinics covering 8 provinces and 22 districts. By June 2016, a total of 317 pharmacies, 30 clinics in 32 districts of the 8 provinces were participating in the PPM network and reported monthly malaria case data. METHODS: This descriptive study documented the process of initiating and maintaining the PPM network in Lao PDR. Epidemiological data reported through the routine surveillance system from January 2009 to June 2016 were analyzed to illustrate the contribution of case reporting from the private sector. RESULTS: A total of 2,301,676 malaria tests were performed in the PPM districts, which included all the PPM pharmacies and clinics (176,224, 7.7%), proportion of patients tested from 14,102 (4.6%) in 2009 to 29,554 (10.4%) in 2015. Over the same period of 90 months, a total of 246,091 positive cases (10.7%) were detected in PPM pharmacies and clinics (33,565; 13.6%), in the same districts as the PPM sites. The results suggest that the PPM sites contributed to a significant increasing proportion of patients positive for malaria from 1687 (7.4%) in 2009 to 5697 (15.8%) in 2015. CONCLUSIONS: Ensuring adequate and timely supplies of RDTs and ACT to PPM sites is critical. Frequent refresher training is necessary to maintain data quality, motivation and feedback. In the context of malaria elimination, the PPM initiative should be expanded further to ensure that all febrile cases seen through the private sector in malaria transmission areas are tested for malaria and treated appropriately. Results from the PPM must be integrated into a centralized registry of malaria cases that should prompt required case and foci investigations and responses to be conducted as part of elimination efforts.

Malaria elimination in Lao PDR: the challenges associated with population mobility.

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 programThis 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.

Thiamin supplementation does not reduce the frequency of adverse events after anti-malarial therapy among patients with falciparum malaria in southern Laos.

BACKGROUND: In a recent study one third of Lao patients presenting with uncomplicated Plasmodium falciparum malaria had biochemical evidence of thiamin deficiency, which was associated with a higher incidence of adverse events. Thiamin supplementation might, therefore, reduce adverse events in this population. METHODS: An exploratory, double-blind, parallel group, placebo-controlled, superiority trial of thiamin supplementation in patients of all ages with uncomplicated and severe falciparum malaria was conducted in Xepon District, Savannakhet Province, southern Laos. Patients were randomly assigned to either oral thiamin 10 mg/day for 7 days immediately after standard anti-malarial treatment then 5 mg daily until day 42, or identical oral placebo. RESULTS: After interim analyses when 630 patients (314 in thiamin and 316 in placebo groups) had been recruited, the trial was discontinued on the grounds of futility. On admission biochemical thiamin deficiency (alpha ≥ 25%) was present in 27% of patients and 9% had severe deficiency (alpha > 31%). After 42 days of treatment, the frequency of thiamin deficiency was lower in the thiamin (2%, 1% severe) compared to the placebo (11%, 3% severe) groups (p < 0.001 and p = 0.05), respectively. Except for diarrhoea, 7% in the placebo compared to 3% in the thiamin group (p = 0.04), and dizziness on day 1 (33% vs 25%, p = 0.045), all adverse events were not significantly different between the groups (p > 0.05). Clinical, haematological, and parasitological responses to treatment did not differ significantly between the two groups. CONCLUSION: Thiamin supplementation reduced biochemical thiamin deficiency among Lao malaria patients following anti-malarial drug treatment, but it did not reduce the frequency of adverse events after anti-malarial therapy or have any detected clinical or parasitological impact. TRIAL REGISTRATION: ISRCTN 85411059.