Xu Meimei, Yu Weiwei, Tong Shilu, Jia Lei, Liang Fengchao, Pan Xiaochuan
Department of Occupational and Environmental Health, School of Public Health, Peking University, Beijing 100191, China.
Epidemiology and Biostatistics Discipline, School of Population Health, University of Queensland, Brisbane, QLD 4006, Australia.
PLoS One. 2015 May 26;10(5):e0126171. doi: 10.1371/journal.pone.0126171. eCollection 2015.
Hand, foot and mouth disease (HFMD) was listed as a notifiable communicable disease in 2008 and is an emerging public health problem in China, especially for children. However, few data are available on the risk assessment of the potential reasons for HFMD in Beijing. This study examined the association of temperature with the incidence of children's HFMD in Beijing at the daily scale for the first time.
A newly developed case-crossover design with a distributed lag nonlinear model (DLNM) was used to assess the delayed and cumulative associations of daily temperature with gender- and age-specific HFMD in Beijing, China, during 2010-2012. Relative humidity, day of the week, public holiday, season and long-term trends were controlled in the model.
Among the total of 113,475 cases, the ratio between males and females was 1.52:1. HFMD was more prevalent in May-July. The temperature-HFMD relationships were non-linear in most age groups except for children aged 6-15 years, with a peak at 25.0~27.5°C. The high-temperature risks were greater, appeared earlier and lasted longer than the low-temperature risks. The relative risks for female children and those aged 6-15 years were higher than those among other groups.
Rising temperatures increased the incidence of children's HFMD, with the largest association at 25.0~27.5°C. Females and children aged 6-15 years were more vulnerable to changes in temperature with regard to the transmission of HFMD than males and other age groups, respectively. Further studies are warranted to confirm these findings in other populations.
手足口病（HFMD）于2008年被列为法定传染病，在中国尤其是儿童中是一个新出现的公共卫生问题。然而，关于北京手足口病潜在病因风险评估的数据很少。本研究首次在日尺度上考察了温度与北京儿童手足口病发病率之间的关联。
采用一种新开发的病例交叉设计与分布滞后非线性模型（DLNM），来评估2010 - 2012年期间中国北京每日温度与性别和年龄特异性手足口病之间的延迟和累积关联。模型中控制了相对湿度、星期几、公共假日、季节和长期趋势。
在总共113475例病例中，男女比例为1.52:1。手足口病在5 - 7月更为流行。除6 - 15岁儿童外，大多数年龄组的温度与手足口病的关系呈非线性，在25.0~27.5°C时达到峰值。高温风险比低温风险更大、出现更早且持续时间更长。女童和6 - 15岁儿童的相对风险高于其他组。
气温升高增加了儿童手足口病的发病率，在25.0~27.5°C时关联最大。就手足口病传播而言，女性和6 - 15岁儿童分别比男性和其他年龄组更容易受到温度变化的影响。有必要进行进一步研究以在其他人群中证实这些发现。
