{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,3]],"date-time":"2026-09-03T17:56:41Z","timestamp":1788458201468,"version":"build-2803163510"},"reference-count":33,"publisher":"Public Library of Science (PLoS)","issue":"2","license":[{"start":{"date-parts":[[2026,2,20]],"date-time":"2026-02-20T00:00:00Z","timestamp":1771545600000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS One"],"abstract":"\n Background<\/jats:title>\n Dengue fever in Bangladesh has escalated from sporadic outbreaks to a persistent, nationwide health crisis. Traditional epidemiological analyses often assume a constant transmission regime, potentially overlooking fundamental shifts driven by viral, environmental, or societal factors. This population-level ecological time-series observational study aimed to identify and characterize significant structural breaks in the time series of dengue admissions in Bangladesh to define distinct epidemiological phases.<\/jats:p>\n <\/jats:sec>\n \n Methods<\/jats:title>\n \n Monthly dengue hospital admission data (January 2008\n \u2500<\/jats:bold>\n October 2025) were obtained from the Institute of Epidemiology, Disease Control and Research (IEDCR) and Directorate General of Health Services (DGHS) public archives. Analyses included STL seasonal-trend decomposition, the Zivot-Andrews unit root test (primary break detection), multi-algorithm breakpoint detection (PELT, Binary Segmentation, Window-based), K-means clustering (optimal at 3 clusters, silhouette score 0.867), and Markov regime-switching models.\n <\/jats:p>\n <\/jats:sec>\n \n Findings<\/jats:title>\n \n Ten structural breaks were identified through a consensus ranking approach. The most prominent break occurred in May 2021 (consensus score\u2009=\u20093). The Markov regime-switching model delineated three distinct transmission regimes: 1) a Low Baseline Regime (2008\n \u2500<\/jats:bold>\n 2023) with a mean of 47 monthly cases (95% CI: 36\n \u2500<\/jats:bold>\n 57); 2) an Intermediate Regime (2008\n \u2500<\/jats:bold>\n 2025) with a mean of 1,288 monthly cases (95% CI: 927\n \u2500<\/jats:bold>\n 1,648); and 3) a Hyperendemic Regime (2019\n \u2500<\/jats:bold>\n 2025) with a mean of 26,127 monthly cases (95% CI: 17,207\u250035,048), representing a 556-fold increase over the low baseline. Seasonality strength was moderate (0.335), but the peak-to-trough seasonal ratio approached 180, indicating pronounced annual epidemic cycles superimposed on the substantially elevated baseline.\n <\/jats:p>\n <\/jats:sec>\n \n Interpretation<\/jats:title>\n Bangladesh has experienced an established regime shift to sustained hyperendemic dengue transmission (persistent as of October 2025) necessitating a fundamental shift from outbreak-response to sustained, year-round control strategies. It is most likely influenced by viral, environmental, and societal factors including documented serotype redistribution. Public health strategies must transition from outbreak-response to sustained high-transmission management, including year-round vector control with pre-monsoon intensification.<\/jats:p>\n <\/jats:sec>","DOI":"10.1371\/journal.pone.0343246","type":"journal-article","created":{"date-parts":[[2026,2,20]],"date-time":"2026-02-20T18:36:47Z","timestamp":1771612607000},"page":"e0343246","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":1,"title":["The emergence of hyperendemic dengue in Bangladesh: An ecological study of structural breaks and transmission regime shifts, 2008\u20132025"],"prefix":"10.1371","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1765-8477","authenticated-orcid":true,"given":"Pratyay","family":"Hasan","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tazdin Delwar","family":"Khan","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mohd.","family":"Arifuzzaman","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Md. 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