The Aggeu Magalhães Research Center -FIOCRUZ/PE, Av. Professor Moraes Rego, s/n Cidade Universitária, Recife, Pernambuco, CEP 50.740-465, Brazil.
Pan American Health Organization, Setor de Embaixadas Norte, Lote 19, Brasília, CEP 70800-400, Brazil.
BMC Public Health. 2018 Jan 12;18(1):130. doi: 10.1186/s12889-018-5039-z.
Starting in August 2015, there was an increase in the number of cases of neonatal microcephaly in Northeast Brazil. These findings were identified as being an epidemic of microcephaly related to Zika virus (ZIKV) infection. The present study aims to analyse the spatial distribution of microcephaly cases in Recife (2015-2016), which is in Northeast Brazil, and its association with the living conditions in this city.
This was an ecological study that used data from reported cases of microcephaly from the State Health Department of Pernambuco (August 2015 to July 2016). The basic spatial unit of analysis was the 94 districts of Recife. The case definition of microcephaly was: neonates with a head circumference of less than the cut-off point of -2 standard deviations below the mean value from the established Fenton growth curve. As an indicator of the living conditions of the 94 districts, the percentage of heads of households with an income of less than twice the minimum wage was calculated. The districts were classified into four homogeneous strata using the K-means clustering algorithm. We plotted the locations of each microcephaly case over a layer of living conditions.
During the study period, 347 microcephaly cases were reported, of which 142 (40.9%) fulfilled the definition of a microcephaly case. Stratification of the 94 districts resulted in the identification of four strata. The highest stratum in relation to the living conditions presented the lowest prevalence rate of microcephaly, and the overall difference between this rate and the rates of the other strata was statistically significant. The results of the Kruskal-Wallis test demonstrated that there was a strong association between a higher prevalence of microcephaly and poor living conditions. After the first 6 months of the study period, there were no microcephaly cases recorded within the population living in the richest socio-economic strata.
This study showed that those residing in areas with precarious living conditions had a higher prevalence of microcephaly compared with populations with better living conditions.
自 2015 年 8 月起，巴西东北部新生儿小头畸形病例数量有所增加。这些发现被认为是与寨卡病毒（ZIKV）感染相关的小头畸形流行。本研究旨在分析巴西东北部累西腓（2015-2016 年）小头畸形病例的空间分布及其与该市生活条件的关系。
这是一项生态研究，使用了伯南布哥州卫生局报告的小头畸形病例数据（2015 年 8 月至 2016 年 7 月）。分析的基本空间单位是累西腓的 94 个区。小头畸形的病例定义为：头围小于从既定 Fenton 生长曲线得出的平均值减去 2 个标准差以下的新生儿。作为 94 个区生活条件的指标，计算了收入低于最低工资两倍的家庭户主百分比。使用 K-均值聚类算法将区分为四个同质层。我们将每个小头畸形病例的位置绘制在一层生活条件上。
在研究期间，报告了 347 例小头畸形病例，其中 142 例（40.9%）符合小头畸形病例的定义。94 个区的分层导致确定了四个层。与生活条件相关的最高层呈现出最低的小头畸形患病率，并且该比率与其他层的比率之间的总体差异具有统计学意义。Kruskal-Wallis 检验的结果表明，较高的小头畸形患病率与较差的生活条件之间存在很强的关联。在研究期间的头 6 个月后，生活在最富裕社会经济阶层的人群中没有记录到小头畸形病例。
本研究表明，与生活条件较好的人群相比，居住在生活条件较差地区的人群小头畸形的患病率更高。
