Gil José F, Palacios Maximiliano, Krolewiecki Alejandro J, Cortada Pedro, Flores Rosana, Jaime Cesar, Arias Luis, Villalpando Carlos, Alberti DÁmato Anahí M, Nasser Julio R, Aparicio Juan P
Instituto de Investigaciones en Enfermedades Tropicales, Sede Regional Orán, Universidad Nacional de Salta, 4530 Salta, Argentina; Instituto de Investigaciones en Energía no Convencional (INENCO-CONICET), Universidad Nacional de Salta, 4400 Salta, Argentina.
Instituto de Investigaciones en Energía no Convencional (INENCO-CONICET), Universidad Nacional de Salta, 4400 Salta, Argentina.
Acta Trop. 2016 Jun;158:24-31. doi: 10.1016/j.actatropica.2016.02.003. Epub 2016 Feb 11.
After more than eighty years dengue reemerged in Argentina in 1997. Since then, the largest epidemic in terms of geographical extent, magnitude and mortality, was recorded in 2009. In this report we analyzed the DEN-1 epidemic spread in Orán, a mid-size city in a non-endemic tropical area in Northern Argentina, and its correlation with demographic and socioeconomic factors. Cases were diagnosed by ELISA between January and June 2009. We applied a space-time and spatial scan statistic under a Poisson model. Possible association between dengue incidence and socio-economic variables was studied with the Spearman correlation test. The epidemic started from an imported case from Bolivia and space-time analysis detected two clusters: one on February and other in April (in the south and the northeast of the city respectively) with risk ratios of 25.24 and 4.07 (p<0.01). Subsequent cases spread widely around the city without significant space-temporal clustering. Maximum values of the entomological indices were observed in January, at the beginning of the epidemic (B=21.96; LH=8.39). No statistically significant association between socioeconomic variables and dengue incidence was found but positive correlation between population size and the number of cases (p<0.05) was detected. Two mechanisms may explain the observed pattern of epidemic spread in this non-endemic tropical city: a) Short range dispersal of mosquitoes and people generates clusters of cases and b) long-distance (within the city) human movement contributes to a quasi-random distribution of cases.
1997年，登革热在阿根廷再度出现，距其首次出现已过去八十多年。自那时起，2009年记录了地理范围、规模和死亡率方面最大的疫情。在本报告中，我们分析了登革热-1型在奥兰的疫情传播情况，奥兰是阿根廷北部非流行热带地区的一个中等规模城市，并分析了其与人口和社会经济因素的相关性。2009年1月至6月期间通过酶联免疫吸附测定法诊断病例。我们在泊松模型下应用了时空和空间扫描统计。通过斯皮尔曼相关性检验研究了登革热发病率与社会经济变量之间可能的关联。疫情始于一例来自玻利维亚的输入病例，时空分析检测到两个聚集区：一个在2月，另一个在4月（分别位于城市的南部和东北部），风险比分别为25.24和4.07（p<0.01）。随后的病例在城市中广泛传播，没有明显的时空聚集。在疫情开始的1月观察到昆虫学指数的最大值（布雷图指数=21.96；房屋指数=8.39）。未发现社会经济变量与登革热发病率之间存在统计学上的显著关联，但检测到人口规模与病例数之间存在正相关（p<0.05）。两种机制可以解释在这个非流行热带城市观察到的疫情传播模式：a）蚊子和人的短距离扩散产生病例聚集区，b）城市内的长距离人员流动导致病例的准随机分布。
