Short-term effects of meteorological factors on children hand, foot and mouth disease in Guangzhou, China

Abstract

Hand, foot and mouth disease (HFMD) is a contagious viral illness that commonly affects infants and children. The underlying risk factors have not yet been systematically examined. This study analyzed the short-term effects of meteorological factors on children HFMD in Guangzhou, China. Daily count of HFMD among children younger than 15 years and meteorological variables from 2009 to 2011 were collected to construct the time series. A generalized additive model was applied to estimate the effects of meteorological factors on HFMD occurrence, after adjusting for long-term trend, seasonal trend, day of week, and public holidays. A negative association between temperature and children HFMD occurrence was observed at lag days 1-3, with the relative risk (RR) for a 1 °C increase on lag day 2 being 0.983 (95% confidence intervals (CI) 0.977 to 0.989); positive effect was found for temperature at lag days 5-9, with the highest effect at lag day 6 (RR = 1.014, 95% CI 1.006 to 1.023). Higher humidity was associated with increased HFMD at lag days 3-10, with the highest effect at lag day 8 (RR = 1.009 for 1% increase in relative humidity, 95% CI 1.007 to 1.010). And we also observed significant positive effect for rainfall at lag days 4 and 8 (RR = 1.001, 95% CI 1.000 to 1.002) for 1-mm increase. Subgroup analyses showed that the positive effects of temperature were more pronounced among younger children. This study suggests that meteorological factors might be important predictors of children HFMD occurrence in Guangzhou.

Socio-ecological factors and hand, foot and mouth disease in dry climate regions: a Bayesian spatial approach in Gansu, China

“…However, another study on the short-term effects of daily meteorological factors on the HFMD showed relative humidity had a negative effect at lag 1 day and positive effects on lag 5-7 days (Wu et al 2014). A similar association between relative humidity and the HFMD was observed in two other studies (Chen et al 2014;Li et al 2014). Additionally, the association between ecological factors and HFMD has a non-linear relationship, which was not analyzed in this study (Li et al 2015;Zhang et al 2016).…”

The Association between Ambient Temperature and Childhood Hand, Foot and Mouth Disease in Chengdu, China: A Distributed Lag Non-linear Analysis

“…The final composition of the function was a natural cubic spline of temperature with five df and a natural cubic spline with three df for lag days. Previous studies specified the lagged effect of temperature from 13 days to 6 weeks of lag14252627. In this study, we found the effect of temperature on childhood HFMD was negligible for lags above 30 days, so a maximum lag of 30 days was used to explore the potential lag associations.…”

Is high relative humidity associated with childhood hand, foot, and mouth disease in rural and urban areas?

“…HFMD case was diagnosed by clinical symptoms, according to Chinese Ministry of Health, including vesicular lesions on hands, feet, mouth (which were often ulcerated), and buttocks. 11,14 A recent research showed that the reporting completeness of CDC can reach 99.84% and the accuracy of the information reported can reach 92.76%. 15 In addition, data of daily temperature and relative humidity were retrieved from Hefei city Bureau of Meteorology.…”

“…10 Based on a prior study, humidity was associated with increased HFMD at lag days 3e10, with the highest effect at lag day eight (RR ¼ 1.009 for 1% increase in relative humidity, 95% confident interval: 1.007e1.010). 11 So the authors speculated that relative humidity might be a critical weather condition for enteroviruses' survival, reproduction and spread, which might cause HFMD epidemic. 12 The association of relative humidity with childhood HFMD in developing cities has not been known.…”