https://scholarworks.bwise.kr/hanyang/handle/2021.sw.hanyang/312 2026-07-03T23:42:50Z https://scholarworks.bwise.kr/hanyang/handle/2021.sw.hanyang/212750 Title: Climate drivers and winter constraints of dengue epidemics: a 10-year epidemiological perspective study in the Lao People's Democratic Republic Authors: Houatthongkham, Souphatsone; Kim, Jae Hyun; Khamphaphongphane, Bouaphanh; Xangsayarath, Phonepadith; Kim, Jong-Hun; Kim, Sung Hye Abstract: BackgroundDengue fever is hyperendemic in the Lao People's Democratic Republic (PDR), where transmission is driven by Aedes mosquitoes and influenced by large-scale climatic phenomena, including the El Ni & ntilde;o-Southern Oscillation (ENSO) and the Indian Ocean Dipole (IOD). As a landlocked nation, the Lao PDR experiences sharper winter temperature declines than coastal regions, which may impose a seasonal "bottleneck" on vector survival and dengue transmission. This study examined whether winter minimum temperatures act as a seasonal transmission bottleneck, alongside the Oceanic Ni & ntilde;o Index (ONI) and the Dipole Mode Index (DMI), during 2014-2023.MethodsMonthly dengue case counts reported to the National Center for Laboratory and Epidemiology, Ministry of Health, Lao PDR, from January 2014 to December 2023 were analyzed using region-specific quasi-Poisson distributed lag nonlinear models. Models incorporated 3-month-lagged ONI/DMI cross-basis functions, winter minimum temperature hinges, long-term trends, and seasonality, with population as an offset. Region-specific estimates were pooled using multivariate meta-analysis to generate best linear unbiased predictions (BLUPs). Optimal lag structures and temperature thresholds were selected by minimizing the quasi-Akaike information criterion and residual sum of squares.ResultsA total of 134,093 dengue cases were reported, with substantial regional heterogeneity. The Capital Region had the highest burden (40,672 cases; annual incidence 35.4 per 100,000), followed by the Southern Mountains and Tropical Rainforests region (20,176 cases; 23.3 per 100,000). Annual incidence in each region appeared constrained by region-specific winter minimum temperature thresholds. Pooled BLUPs analyses adjusted for covariates revealed monotonic cumulative relative risk increases with ONI [RR = 2.83 at ONI = 2.0; 95% confidence interval (CI): 1.46-5.49) and decreases with DMI (RR = 0.37 at DMI = 1.5; 95% CI: 0.24-0.59).ConclusionsWinter cold functions as a primary bottleneck for dengue transmission in the Lao PDR, with ENSO amplifying and IOD suppressing outbreak risk. These findings support the development of climate-integrated, region-specific early warning systems. Incorporating 3-month-lagged climate indices may enhance public health preparedness for future dengue outbreaks. 2026-05-01T00:00:00Z https://scholarworks.bwise.kr/hanyang/handle/2021.sw.hanyang/209137 Title: Determinants of the lost to follow-up status among patients with tuberculosis who emigrated to the Republic of Korea: a mixed-method study Authors: Jeon, Sumin; Lee, Ji Yeon; Jeong, Ina; Sin, Sooim; Lee, Inhan; Kim, Younghyun; Han, Ah Yeon; Lee, Seung-Eun; Seo, Soonryu; Kim, Hyungjun; Kwon, Yunhyung; Song, Chieeun; Joh, Joon-Sung; Kim, Sung Hye Abstract: Introduction Tuberculosis (TB) remains a significant global health concern, with foreign migrants in the Republic of Korea (ROK) representing a particularly vulnerable group; despite comprising only 3.5% of the population, they account for over 5% of annual TB cases and exhibit disproportionately high rates of lost to follow up (LTFU) from treatment compared to native Koreans. This mixed-methods study aimed to identify key factors influencing non-adherence to treatment and LTFU among migrants.Methods Utilizing national TB surveillance data from 2016 to 2018 for 4,011 migrant and 64,620 native patients, quantitative analysis were employed to identify factors associated with LTFU for migrants. Complementary in-depth qualitative interviews with Public-Private Mix (PPM) nurses provided deeper insights into barriers to adherence.Results The study revealed a significantly higher LTFU rate (21.5%) among migrant patients compared to domestic patients (2.3%). Key contributing factors included nationality (highest crude odds for migrants from Thailand, Central, and North Asia), living arrangements (increased risk for those not with family or living alone), and male gender. Drug-resistant TB made patients over four times more likely to discontinue treatment and systemic issues such as frequent care transfers and the presence of comorbidities. Qualitative findings highlighted inadequate patient education and misconceptions about TB severity (often seen as a "mild cold"), leading to premature discontinuation. Poor medical interpretation services and low awareness among migrants of free TB treatment under the PPM program were also critical barriers.Discussion These findings imply that high LTFU among migrant patients is multifactorial, stemming from personal, clinical, and systemic issues. Addressing this disparity requires targeted interventions, including culturally tailored multilingual educational campaigns, improved medical interpretation, and increased awareness of PPM program eligibility and free treatment. Streamlining interfacility care transfer processes (such as the "Tuberculosis Relief Belt" initiative), expanding PPM coverage, and ensuring access to specialized care for comorbid conditions are also essential. Addressing these multifaceted challenges is critical to reducing LTFU rates and enhancing treatment continuity and outcomes, thereby advancing TB control efforts in ROK's shifting migration context. 2025-09-01T00:00:00Z https://scholarworks.bwise.kr/hanyang/handle/2021.sw.hanyang/208663 Title: Incomplete antenatal care despite high coverage: geographic and sociocultural barriers in Lao PDR Authors: Kim, Hyunkyong; Han, Hyejung; Phommachan, Khammany; Yang, Yong Sook; Kim, Sung Hye Abstract: Background: Despite progress in maternal health in Lao PDR, timely access and the completeness of antenatal care (ANC) services remain uneven, particularly in remote provinces with high maternal mortality. Understanding the patterns of ANC utilization and barriers to receiving adequate care is essential to inform targeted interventions. Objective: This study examined factors associated with early ANC initiation (<= 12 weeks' gestation), adequate ANC (>= 4 visits), and the coverage of essential ANC components among women in two northern provinces. Methods: In February 2023, we conducted a cross-sectional survey in Xiengkhuang and Huaphanh provinces, using stratified three-stage cluster sampling to recruit 380 women with children under 2 years. Face-to-face interviews collected data on ANC timing and frequency, receipt of 13 Ministry-of-Health-defined ANC services, and education on five key pregnancy danger signs. Descriptive statistics summarized utilization, and multivariable logistic regression identified predictors of timely and adequate ANC. Results: While 95% of participants reported at least one ANC visit and 77.1% had four or more, only 34.5% began ANC within the first trimester. Lack of road access was associated with lower odds of timely and adequate ANC up to 59% (adjusted odds ratio [aOR] for adequate ANC: 0.41; 95% CI: 0.19-0.90). Ethnic minorities, specifically Hmong-Lu Mien women, were associated with 87% reduced odds of having adequate ANC e (aOR: 0.13; 95% CI: 0.02-0.71). Service completeness remained low: just 10.7% reported receiving all essential 13 ANC components, and comprehensive education on all five key pregnancy danger signs was rare (1.5%), and 1.5% reported receiving full education on danger signs; counseling on life-threatening symptoms reached 5.7%. Laboratory services (anemia screening 82.2%, HIV testing 78.4%) and iron supplementation (98%) were common, but only 24.4% reported folic acid provision. Conclusion: Despite significant improvements in overall ANC coverage in Lao PDR, critical gaps persist in timely initiation and completeness of ANC services, particularly among geographically and ethnically marginalized groups. These findings underscore the urgent need for targeted interventions that address both geographic and cultural barriers and enhance the timeliness and completeness of ANC services to reduce disparities and maximize maternal health benefits in resource-limited settings. 2025-07-01T00:00:00Z https://scholarworks.bwise.kr/hanyang/handle/2021.sw.hanyang/207479 Title: Guidance for conducting and evaluating serological surveys to assess interruption of yaws transmission in the context of an eradication target Authors: Mitja, Oriol; Gass, Katherine; Marks, Michael; Cooper, Philip J.; Diggle, Petter J.; Waller, Lance; Agana-Nsiire, Patrick; Dofitas, Belen Lardizabal; Dyson, Louise; Kim, Sung Hye; Jacobson, Julie; Kaldor, John; Vaz Nery, Susana; Revankar, Chandrakant; Sopoh, Ghislain; Solomon, Anthony W.; Dagne, Daniel Argaw; Pathak, Priya; Yajima, Aya; Lin, Zaw; Barogui, Mahoutondji Yves Thierry; Scholte, Ronaldo Carvalho; Sanikullah, Kazim Hizbullah; Drakeley, Chris; Stresman, Gillian; Gyapong, John; Asiedu, Kingsley Bampoe Abstract: This document provides a summary of guidance developed for national programmes on conducting serosurveys to assess yaws transmission status, with the objective of confirming yaws seroprevalence below 1% at each of three serosurveys over a period of 3-10 years after reporting the last case of active yaws in a region. It proposes active testing of children aged 1-5 years through population-based surveys and includes recommendations on survey design, sample size determination, sampling of primary sampling units (PSUs) within an evaluation unit, sampling of households within PSUs, integration with existing public health surveys, and follow-up protocols for positive results. Geospatial analysis and sustained surveillance are recommended for accurate assessment of whether transmission interruption has been achieved. 2025-04-01T00:00:00Z