Ferreira Marcos C
Campinas State University - UNICAMP, Geosciences Institute, Department of Geography, Campinas, São Paulo, Brazil.
Geospat Health. 2014 Nov;9(1):141-51. doi: 10.4081/gh.2014.12.
El Niño South Oscillation (ENSO) is one climatic phenomenon related to the inter-annual variability of global meteorological patterns influencing sea surface temperature and rainfall variability. It influences human health indirectly through extreme temperature and moisture conditions that may accelerate the spread of some vector-borne viral diseases, like dengue fever (DF). This work examines the spatial distribution of association between ENSO and DF in the countries of the Americas during 1995-2004, which includes the 1997-1998 El Niño, one of the most important climatic events of 20(th) century. Data regarding the South Oscillation index (SOI), indicating El Niño-La Niña activity, were obtained from Australian Bureau of Meteorology. The annual DF incidence (AIy) by country was computed using Pan-American Health Association data. SOI and AIy values were standardised as deviations from the mean and plotted in bars-line graphics. The regression coefficient values between SOI and AIy (rSOI,AI) were calculated and spatially interpolated by an inverse distance weighted algorithm. The results indicate that among the five years registering high number of cases (1998, 2002, 2001, 2003 and 1997), four had El Niño activity. In the southern hemisphere, the annual spatial weighted mean centre of epidemics moved southward, from 6° 31' S in 1995 to 21° 12' S in 1999 and the rSOI,AI values were negative in Cuba, Belize, Guyana and Costa Rica, indicating a synchrony between higher DF incidence rates and a higher El Niño activity. The rSOI,AI map allows visualisation of a graded surface with higher values of ENSO-DF associations for Mexico, Central America, northern Caribbean islands and the extreme north-northwest of South America.
厄尔尼诺南方涛动（ENSO）是一种与全球气象模式年际变化相关的气候现象，它影响着海面温度和降雨变化。它通过极端温度和湿度条件间接影响人类健康，这些条件可能会加速一些媒介传播的病毒性疾病的传播，如登革热（DF）。这项工作研究了1995年至2004年期间美洲国家ENSO与DF之间关联的空间分布，其中包括20世纪最重要的气候事件之一——1997 - 1998年厄尔尼诺事件。关于南方涛动指数（SOI）的数据，该数据表明厄尔尼诺 - 拉尼娜活动情况，是从澳大利亚气象局获取的。各国的年度登革热发病率（AIy）是使用泛美卫生组织的数据计算得出的。SOI和AIy值被标准化为相对于均值的偏差，并绘制在柱状线图中。计算了SOI与AIy之间的回归系数值（rSOI,AI），并通过反距离加权算法进行空间插值。结果表明，在记录病例数较多的五年（1998年、2002年、2001年、2003年和1997年）中，有四年出现了厄尔尼诺活动。在南半球，年度空间加权平均流行中心向南移动，从1995年的南纬6°31′移至1999年的南纬21°12′，并且在古巴、伯利兹、圭亚那和哥斯达黎加，rSOI,AI值为负，这表明登革热发病率较高与厄尔尼诺活动较强之间存在同步性。rSOI,AI地图可以直观呈现出一个渐变表面，墨西哥、中美洲、加勒比海北部岛屿以及南美洲最西北端的ENSO - DF关联值较高。
