Environmental Health Institute, National Environment Agency, Singapore 138667, Singapore.
Manaaki Whenua-Landcare Research, Lincoln P.O. Box 69040, New Zealand.
Viruses. 2022 Nov 4;14(11):2450. doi: 10.3390/v14112450.
Dengue is a major vector-borne disease worldwide. Here, we examined the spatial distribution of extreme weekly dengue outbreak risk in Singapore from 2007 to 2020. We divided Singapore into equal-sized hexagons with a circumradius of 165 m and obtained the weekly number of dengue cases and the surface characteristics of each hexagon. We accounted for spatial heterogeneity using max-stable processes. The 5-, 10-, 20-, and 30-year return levels, or the weekly dengue case counts expected to be exceeded once every 5, 10, 20, and 30 years, respectively, were determined for each hexagon conditional on their surface characteristics remaining constant over time. The return levels were higher in the country's east, with the maximum weekly dengue cases per hexagon expected to exceed 51 at least once in 30 years in many areas. The surface characteristics with the largest impact on outbreak risk were the age of public apartments and the percentage of impervious surfaces, where a 3-year and 10% increase in each characteristic resulted in a 3.8% and 3.3% increase in risk, respectively. Vector control efforts should be prioritized in older residential estates and places with large contiguous masses of built-up environments. Our findings indicate the likely scale of outbreaks in the long term.
登革热是全球主要的虫媒传染病。在这里，我们研究了 2007 年至 2020 年新加坡每周登革热爆发风险的极端空间分布。我们将新加坡划分为边长为 165 米的正六边形，并获得了每周的登革热病例数和每个六边形的地表特征。我们使用最大稳定过程来解释空间异质性。在六边形的表面特征随时间保持不变的情况下，确定了每个六边形的 5 年、10 年、20 年和 30 年的重现水平，即预计每 5、10、20 和 30 年分别会超过一次的每周登革热病例数。该国东部的重现水平更高，在许多地区，每个六边形预计至少有一次在 30 年内每周的登革热病例数超过 51 例。对爆发风险影响最大的地表特征是公共公寓的年龄和不透水面的比例，每增加 3 年和 10%，风险分别增加 3.8%和 3.3%。应优先考虑在老旧住宅区和大面积建成环境集中的地方开展病媒控制工作。我们的研究结果表明了长期内可能发生的疫情规模。
