Location, seasonal and functional characteristics of water-holding containers with juvenile Aedes albopictus in urban southern Taiwan: a cross-sectional study

Background: Urban Kaohsiung City (KC), in southern Taiwan, has experienced annual dengue epidemics for decades despite considerable vector control efforts. Substantial research has been undertaken to characterize Aedes aegypti breeding habitats, but no systematic assessment has been completed for Aedes albopictus present in KC. Methods: A cross-sectional survey was conducted from 2013 to 2015 in a predefined area of KC. Each identified container was characterised by season, location, ownership, function and number of juvenile A. aegypti. Negative binomial hurdle analyses were applied to evaluate the association between the number of juvenile A. albopictus and the characteristics of each identified container. Results: For all containers, high numbers of A. albopictus were significantly predicted by containers identified during the wet season (vs dry), located on government (vs private) property and classified as a discarded item (vs water storage). For outdoor containers, more A. albopictus were significantly predicted by wet season (vs dry) and discarded item (vs container in use). Conclusions: In order to improve dengue prevention in KC, we propose that vector control efforts be expanded to include A. albopictus through an increased focus during the wet season on discarded containers that are located outdoors and on government property.