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Volume 32, Number 4—April 2026
Research
Dengue Incidence, Seroprevalence, and Expansion Factors from Active Surveillance, Brazil, 2016–2021
Figure 3

Figure 3. Locations of DEN-03-IB clinical study sites and expansion factors by municipality, Brazil, 2016–2021. A) Locations of clinical sites that enrolled participants in the DEN-03-IB phase 3 study of a live attenuated tetravalent dengue vaccine, Butantan-DV, in the 5 geographic regions (North, Northeast, Center-West, Southeast, South). B, C) Expansion factors and 95% CIs by municipality for the entire study period 2016–2021 (B) and during an outbreak year, 2019 (C). Note that 2 clinical sites were located in São Paulo and that Laranjeiras was the municipality closest to the clinical site in Aracaju.
1Preliminary results from this study were presented at the American Society for Tropical Medicine and Hygiene annual meeting; November 13–17, 2024, New Orleans, Louisiana, USA.