AUTHOR=Anderson Kathryn B. , Stewart-Ibarra Anna M. , Buddhari Darunee , Beltran Ayala Efrain Felix , Sippy Rachel J. , Iamsirithaworn Sopon , Ryan Sadie J. , Fernandez Stefan , Jarman Richard G. , Thomas Stephen J. , Endy Timothy P. TITLE=Key Findings and Comparisons From Analogous Case-Cluster Studies for Dengue Virus Infection Conducted in Machala, Ecuador, and Kamphaeng Phet, Thailand JOURNAL=Frontiers in Public Health VOLUME=8 YEAR=2020 URL=https://www.frontiersin.org/journals/public-health/articles/10.3389/fpubh.2020.00002 DOI=10.3389/fpubh.2020.00002 ISSN=2296-2565 ABSTRACT=

Dengue viruses (DENV) pose a significant and increasing threat to human health across broad regions of the globe. Currently, prevention, control, and treatment strategies are limited. Promising interventions are on the horizon, including multiple vaccine candidates under development and a renewed and innovative focus on controlling the vector, Aedes aegypti. However, significant gaps persist in our understanding of the similarities and differences in DENV epidemiology across regions of potential implementation and evaluation. In this manuscript, we highlight and compare findings from two analogous cluster-based studies for DENV transmission and pathogenesis conducted in Thailand and Ecuador to identify key features and questions for further pursuit. Despite a remarkably similar incidence of DENV infection among enrolled neighborhood contacts at the two sites, we note a higher occurrence of secondary infection and severe illness in Thailand compared to Ecuador. A higher force of infection in Thailand, defined as the incidence of infection among susceptible individuals, is suggested by the higher number of captured Aedes mosquitoes per household, the increasing proportion of asymptomatic infections with advancing age, and the high proportion of infections identified as secondary-type infections by serology. These observations should be confirmed in long-term, parallel prospective cohort studies conducted across regions, which would advantageously permit characterization of baseline immune status (susceptibility) and contemporaneous assessment of risks and risk factors for dengue illness.