A-Z Index × Submit A-Z Index × Submit A-Z Index Search Dropdown × Submit Facebook Twitter LinkedIn Syndicate Emerging Infectious Disease journal ISSN: 1080-6059 Disclaimer: Early release articles are not considered as final versions. Any changes will be reflected in the online version in the month the article is officially released.
We evaluated the transmission dynamics of dengue virus (DENV) during 2010–2025 in Ceará State, Brazil. Ceará has been a dengue hyperendemic region, where all 4 DENV serotypes co-circulate, predominantly DENV-1 and DENV-2, and where DENV-3 was recently reintroduced. Our findings provide an epidemiologic baseline for postlicensure dengue vaccine evaluation.
Dengue virus (DENV) is an arbovirus estimated to cause >390 million infections annually worldwide, leading to >10,000 deaths in >125 countries ( 1 , 2 ). DENV (Flaviviridae family) is transmitted to humans primarily by Aedes aegypti and Ae. albopictus mosquitoes ( 3 ) and comprises 4 genetically and antigenically distinct serotypes (DENV-1–4) ( 4 ). DENV infection can be categorized as dengue without warning signs, dengue with warning signs, and severe dengue, which can include death ( 5 ). No specific antiviral treatment is available for dengue. As of August 2026, Dengvaxia (Sanofi Pasteur, https://www.sanofi.us ), Qdenga TAK-003 (Takeda, https://www.takeda.com ), and Butantan-DV (Instituto Butantan, https://en.butantan.gov.br ) are 3 licensed vaccines to prevent dengue; however, Dengvaxia use remains limited because of safety concerns ( 6 , 7 ). Brazil remains one of the most affected countries by dengue and has annual epidemics, widespread vector distribution, and co-circulation of all 4 DENV serotypes ( 8 ). We integrate epidemiologic and genomic methods to investigate DENV transmission dynamics during 2010–2025 in Ceará, a hyperendemic state in Brazil.
We retroactively obtained national epidemiologic data on laboratory-confirmed dengue cases during January 2010–January 2025 from Brazil’s Ministry of Health. We obtained additional epidemiologic data from the Central Laboratory of Public Health of Ceará for dengue cases reported during July 2014–June 2025. We used the MiSeq platform (Illumina, https://www.illumina.com ) to sequence residual quantitative reverse transcription PCR–positive DENV serum samples collected from case-patients with DENV-1–3 serotypes during February 2024–July 2025. We assigned DENV lineages by using the DENV typing tool ( 9 ), followed by phylogenetic reconstruction. We also performed time-series, spatial mapping, and demographic analyses ( Appendix ).
Figure 1 . Dengue incidence and DENV test positivity from study of DENV transmission dynamics, Ceará State, Brazil, 2010–2025. A) Weekly incidence of laboratory-confirmed dengue cases/100,000 inhabitants at the national (Brazil) and state...
During January 3, 2010–January 25, 2025, Brazil reported 1,657,046 laboratory-confirmed dengue cases across 98.9% (5,509/5,570) of municipalities in all 26 states and the Federal District. We identified 13 major epidemic waves at the national level; annual incidence varied from 4.0 to 190.4 cases/100,000 inhabitants, and the largest epidemic occurred in 2024 ( Figure 1 , panel A). National DENV testing positivity rate ranged from 18.2% (19,460/106,901 inhabitants) to 57.1% (146,649/256,981 inhabitants) during those 15 years ( Figure 1 , panel B). In Ceará, a total of 131,961 laboratory-confirmed cases were reported, corresponding to a cumu…