Assessing Thailand’s 1-3-7 surveillance strategy in accelerating malaria elimination

Abstract

Background: Thailand’s strong malaria elimination program relies on effective implementation of its 1-3-7 surveillance strategy, which was endorsed and implemented nationwide in 2016. For each confirmed malaria patient, the Ministry of Public Health’s Division of Vector Borne Diseases (DVBD) ensures completion of case notification within 1 day, case investigation within 3 days, and foci investigation within 7 days. To date, there has not been a comprehensive assessment of the performance and achievements of the 1-3-7 surveillance strategy although such results could help Thailand’s future malaria elimination strategic planning. Methods: This study examined adherence to the 1-3-7 protocols, tracked progress against set targets, and examined geographic variations in implementation of the 1-3-7 strategy in the program’s initial five years. An auto-regressive integrated moving average (ARIMA) time series analysis with seasonal decomposition assessed the plausible implementation effect of the 1-3-7 strategy on malaria incidence in the program’s initial five years. The quantitative analysis included all confirmed malaria cases from public health and non-governmental community facilities from October 2014 to September 2021 (fiscal year [FY] 2015 to FY 2021) (n = 77,405). The spatial analysis included active foci with known geocoordinates that reported more than five cases from FY 2018 to FY 2021.Results: From FY 2017 to FY 2021, on-time case notification improved from 24.4% to 89.3%, case investigations from 58.0% to 96.5%, and foci investigations from 37.9% to 87.2%. Adherence to timeliness protocols did not show statistically significant variation by area risk classification. However, adherence to 1-3-7 protocols showed a marked spatial heterogeneity among active foci, and the ARIMA model showed a statistically significant acceleration in the reduction of malaria incidence. The 1-3-7 strategy national indicators and targets in Thailand have shown progressive success, and most targets were achieved for FY 2021. Conclusion: The results of Thailand’s 1-3-7 surveillance strategy are associated with a decreased incidence in the period following the adoption of the strategy although there is notable geographic variation. The DVBD will continue to implement and adapt the 1-3-7 strategy to accelerate progress toward malaria elimination. This assessment may be useful for domestic strategic planning and to other countries considering more intensive case and foci investigation and response strategies.

Modelling malaria in southernmost provinces of Thailand: a two-step process for analysis of highly right-skewed data with a large proportion of zeros

“…Other risks may arise from the improper use of insecticide-treated nets or long-lasting insecticidal nets [29][30][31]. Defensive strategies or exposure to malaria prevention techniques used in national malaria control initiatives at the household level may have an impact on lowering the occurrence of malaria [12].…”

“…Even with the fluctuating occurrence and incidence rates of malaria, there appeared to be a downward tendency. This decrease was attributed to national policies for active management of foci, which included the full adoption of the 1-3-7 surveillance method for persistent active foci [12,21,33].…”

“…Thailand has established the goal of eradicating malaria by 2024 and recently announced malaria-free status in 42 of its 77 provinces [12]. Despite this achievement, malaria continues to be concentrated along Thailand's borders, making the effort to eradicate the illness much more difficult.…”

Modelling malaria in southernmost provinces of Thailand: a two-step process for analysis of highly right-skewed data with a large proportion of zeros

“…Other risks may arise from the improper use of insecticide-treated nets or long-lasting insecticidal nets [30][31][32]. Defensive strategies or exposure to malaria prevention techniques used in national malaria control initiatives at the household level may have an impact on lowering the occurrence of malaria [12].…”

“…Thailand has established the goal of eradicating malaria by 2024 and recently announced malaria-free status in 42 of its 77 provinces [12]. Despite this achievement, malaria continues to be concentrated along Thailand's borders, making the effort to eradicate the illness much more di cult.…”