Effect of weather variability on the incidence of mumps in children: a time-series analysis

Abstract

The increasing international interest in the potential health effects of climate change has emphasized the importance of investigations into the relationship between weather variability and infectious diseases. However, few studies have examined the impact of weather variability on mumps in children, despite the fact that children are considered particularly vulnerable to climate change. We acquired data about cases of mumps in children aged <15 years and weather variability in Fukuoka, Japan from 2000 to 2008, and then used time-series analyses to assess how weather variability affected mumps cases, adjusting for seasonal variations, inter-annual variations, and temporal variations of two large epidemics in 2001 and 2004-2005. The weekly number of mumps cases increased by 7·5% (95% CI 4·0-11·1) for every 1°C increase in average temperature and by 1·4% (95% CI 0·5-2·4) for every 1% increase in relative humidity. The percentage increase was greatest in the 0-4 years age group and tended to decrease with increasing age. The number of mumps cases in children increased significantly with increased average temperature and relative humidity.

The association between the incidence of mumps and meteorological parameters in Taiwan

“…13 The discrepancy might be due to the effects of varied seasonal exposure and mutual confounding factors between meteorological factors, which are presented in different areas. 14 We found that the occurrence of mumps was associated with the mean temperature and the vapor pressure in both the regression analysis and the casecrossover study; this result was consistent with a previous study in Japan 14 20 These discordant findings may have resulted from the different methodologies used or whether confounding factors were removed.…”

“…1 It has been shown that the incidence of mumps is influenced by the level of temperature and humidity. 14,20 Increases in temperature and humidity improve the duration of virus survival and virulence in the environment, 8,14 which consequently increases the opportunities for hosts to become infected with mumps. 21,22 In this study, the occurrence of mump virus infection began to increase at 20 C and began to decline if the temperatures were higher than approximately 25 C, producing an inverted V-shaped relationship.…”

“…Mumps is assumed to be transmitted from close contact with infected individuals via hands or from fomites. 8,14 The activity of the mumps virus can last for several months at 4 C yet only one day at 37 C; however, it cannot survive at high temperatures over 55 C. 23 The mechanism of temperature and vapor pressure in the transmission of mumps virus is still unclear. Although several prevention measures have been implemented for mumps in Taiwan including a vaccination program (coverage rate over 90%) and health education, cases of mumps have continued to develop every year.…”

“…Although these phenomena have not been well explained, the seasonality of mumps provides evidence that meteorological factors might play a key role in its occurrence. 14 The effects of weather factors on infectious diseases have received global attention in the context of climate change in recent years. A further understanding of the relationships between meteorological factors and occurrence of mumps could help improve both disease forecasting and preventive efforts.…”

The relationship between meteorological factors and mumps incidence in Guangzhou, China, 2005–2012:

“…Little literature was found on the relationship between meteorological factors and mumps. 19 To access the effects of meteorological factors on the incidence of mumps and find the vulnerable populations, we performed a distributed lag nonlinear time-series analysis.…”