Thailand’s National Malaria Elimination Strategy 2017–2026 introduced the 1-3-7 strategy as a robust surveillance and response approach for elimination that would prioritize timely, evidence-based action. Under this strategy, cases are reported within 1 day, cases are investigated within 3 days, and foci are investigated and responded to within 7 days, building on Thailand’s long history of conducting case investigation since the 1980s. However, the hallmark of the 1-3-7 strategy is timeliness, with strict deadlines for reporting and response to accelerate elimination. This paper outlines Thailand’s experience adapting and implementing the 1-3-7 strategy, including success factors such as a cross-sectoral Steering Committee, participation in a collaborative regional partnership, and flexible local budgets. The programme continues to evolve to ensure prompt and high-quality case management, capacity maintenance, and adequate supply of lifesaving commodities based on surveillance data. Results from implementation suggest the 1-3-7 strategy has contributed to Thailand’s decline in malaria burden; this experience may be useful for other countries aiming to eliminate malaria.

Abstract. We conducted contact tracing and high-risk group screening using pooled real-time polymerase chain reaction (PCR) to support malaria elimination in Thailand. PCR detected more Plasmodium infections than the local and expert microscopists. High-throughput pooling technique reduced costs and allowed prompt reporting of results.Thailand's National Malaria Control and Elimination Strategy aims to free 80% of the country from locally acquired malaria by the year 2020 (Bureau of Vector-Borne Diseases, Ministry of Public Health, Thailand, unpublished data). However, the elimination of local transmission requires rapid detection and treatment of all infections, including those infections in asymptomatic individuals who may serve as important reservoirs.1-3 Currently, malaria case detection for surveillance depends on microscopy or rapid diagnostic tests, but both methods miss low parasite densities on the order of 10 parasites/μL. Such submicroscopic infections are detectable by polymerase chain reaction (PCR) and are common in areas with low and unstable malaria. [4][5][6][7] Efforts to control and eliminate malaria from Trat province on the border with Cambodia are intensifying because of the potential spread of artemisinin resistance. The detection of submicroscopic cases may facilitate containment efforts and help preserve artemisinin-based combination therapies for effective malaria treatment (Bureau of Vector-Borne Diseases, Ministry of Public Health, Thailand, unpublished data).Real-time PCR is a highly sensitive tool for detecting and speciating Plasmodia. Pooling samples before analysis facilitates the large-scale application of this technique for surveillance by reducing cost and analysis time. 7,8 As Thailand aims for malaria elimination, including elimination of artemisininresistant parasites, improvements in case detection are necessary. We aimed to determine if pooled real-time PCR could be integrated with the existing active case detection systems in Thailand and if so, if it would be more effective than microscopy for identifying low-density parasitemias.A single index case, with mixed P. falciparum-P. vivax infection, was identified during hospitalization for severe malaria in July of 2011 through passive case detection. This infection was likely acquired during frequent forest exposure. Two weeks after this identification, 187 residents in Bo Rai district, Trat province, Thailand (Figure 1) were contacted over 3 days according to the policies of the National Malaria Control Program of Thailand, which includes contact tracing (Case Investigation Survey) and high-risk group screening (Special Case Detection). For contact tracing, we screened neighbors within 1 km of the index case. For high-risk group screening, we screened soldiers from Khao Lan and Ban Sapanhin army camps and residents of Takang and Ban Samoh villages, which have a high proportion of Burmese Mon migrants.We administered a questionnaire to collect demographic information and risk factors for malaria, such as history of fever a...

BackgroundThe area along the Thai-Cambodian border is considered an epicenter of anti-malarial drug resistance. Recently, parasite resistance to artemisinin-based therapies has been reported in the area. The artemisinin resistance containment project was initiated in November 2008, with the aim to limit resistant parasites and eliminate malaria in this region. This study describes the response to artemisinin-based therapy among falciparum malaria patients in the area, using data from the malaria surveillance programmed under the containment project.MethodsThe study was conducted in seven provinces of Thailand along the Thai-Cambodian border. Data of Plasmodium falciparum-positive patients during January 2009 to December 2011 were obtained from the electronic malaria information system (eMIS) Web-based reporting system. All P. falciparum cases were followed for 42 days, as the routine case follow-up protocol. The demographic characteristics of the patients were described. Statistical analysis was performed to determine the cure rate of the current standard anti-malarial drug regimen--mefloquine-artesunate combination therapy (MAS). The proportion of patients who remained parasite-positive at each follow-up day was calculated. In addition, factors related to the delayed parasite clearance on day-3 post-treatment, were explored.ResultsA total of 1,709 P. falciparum-positive cases were reported during the study period. Almost 70% of falciparum cases received MAS therapy (n = 1,174). The majority of cases were males, aged between 31 and 50 years. The overall MAS cure rate was >90% over the three-year period. Almost all patients were able to clear the parasite within 7 to 14 days post-treatment. Approximately 14% of patients undergoing MAS remained parasite-positive on day-3. Delayed parasite clearance was not significantly associated with patient gender, age, or citizenship. However, delayed parasite clearance varied across the study area.ConclusionAnti-malarial drug-resistant parasites should be closely monitored in the area along the Thai-Cambodian border. Although the MAS cure rate in this study area was above 90%, an increasing trend of treatment failure has been reported in neighboring parts. Effective malaria surveillance is an important component to monitor drug-resistance in the malaria containment project.