PM(2.5) in Beijing – temporal pattern and its association with influenza

BACKGROUND: Air pollution in Beijing, especially PM(2.5,) has received increasing attention in the past years. Despite Beijing being one of the most polluted cities in the world, there has still been a lack of quantitative research regarding the health impact of PM(2.5) on the impact of diseases in Beijing. In this study, we aimed to characterize temporal pattern of PM(2.5) and its potential association with human influenza in Beijing. METHODS: Based on the data collected on hourly ambient PM(2.5) from year 2008 to 2013 and on monthly human influenza cases from 2008 and 2011, we investigated temporal patterns of PM(2.5) over the five-year period and utilized the wavelet approach to exploring the potential association between PM(2.5) and influenza. RESULTS: Our results found that ambient PM(2.5) pollution was severe in Beijing with PM(2.5) concentrations being significantly higher than the standards of the World Health Organization, the US EPA, and the Chinese EPA in the majority of days during the study period. Furthermore, PM(2.5) concentrations in the winter heating seasons were higher than those in non-heating seasons despite high variations. We also found significant association between ambient PM(2.5) peak and human influenza case increase with a delayed effect (e.g. delayed effect of PM(2.5) on influenza). CONCLUSIONS: Ambient PM(2.5) concentrations were significantly associated with human influenza cases in Beijing, which have important implications for public health and environmental actions.