부산대학교 도서관

In South East Asia, dengue epidemics have increased in size and geographical distribution in recent years. We examined the spatiotemporal distribution and epidemiological characteristics of reported dengue cases in the predominantly rural state of Sabah, in Malaysian Borneo–an area where sylvatic and urban circulation of pathogens are known to intersect. Using a public health data set of routinely notified dengue cases in Sabah between 2010 and 2016, we described demographic and entomological risk factors, both before and after a 2014 change in the clinical case definition for the disease. Annual dengue incidence rates were spatially variable over the 7-year study period from 2010–2016 (state-wide mean annual incidence of 21 cases/100,000 people; range 5-42/100,000), but were highest in rural localities in the western districts of the state (Kuala Penyu, Nabawan, Tenom and Kota Marudu). Eastern districts exhibited lower overall dengue rates, although a high proportion of severe (haemorrhagic) dengue cases (44%) were focused in Sandakan and Tawau. Dengue incidence was highest for those aged between 10 and 29 years (24/100,000), and was slightly higher for males compared to females. Available vector surveillance data indicated that during large outbreaks in 2015 and 2016 the mosquito Aedes albopictus was more prevalent in both urban and rural households (House Index of 64%) than Ae. aegypti (15%). Demographic patterns remained unchanged both before and after the dengue case definition was changed; however, in the years following the change, reported case numbers increased substantially. Overall, these findings suggest that dengue outbreaks in Sabah are increasing in both urban and rural settings. Future studies to better understand the drivers of risk in specific age groups, genders and geographic locations, and to test the potential role of Ae. albopictus in transmission, may help target dengue prevention and control efforts. Author summary: In order to combat the rising regional incidence of dengue in South East Asia, incidence patterns must be better characterised within different ecological settings. We conducted the first retrospective analysis of dengue epidemiology in the predominantly rural state of Sabah, Malaysia, where both urban and sylvatic transmission cycles exist. Human notification data over a 7-year period were reviewed and spatiotemporal and demographic risk factors identified. We found that: 1. While urban habitats do play a role in mediating the spread of dengue in Sabah, cases from both urban and rural localities contributed equally to dengue outbreaks; 2. Human demographic risk factors included being aged between 10 and 29 years, and being male; 3. Cases of severe dengue were more common in the eastern districts of the state–almost half of severe dengue cases were reported from Sandakan and Tawau; and 4. The presence of Aedes albopictus in and around the majority of urban and rural case households, often in the apparent absence of Ae. aegypti, suggests that its role in transmission requires further investigation. This study emphasises that increasing incidence of dengue in urban South East Asia is also mirrored in more rural areas, and suggests a need for control strategies that address both urban and rural dengue risk. [ABSTRACT FROM AUTHOR]