PhD student, National Cheng Kung University/Department of Environmental and Occupational Health
To examine the differences of the effects between indoor and ambient absolute humidity on Influenza.
The average (sd) levels of ambient and estimated-indoor absolute humidity (AH) were 15.99 (3.699) and 16.53 (2.70), respectively. The result showed that every 10 g/m3 decrease of ambient AH was associated with the increase of 1.1 case of influenza (β = -1.1162; 95 % C.I. = -2.0536, -0.1788). Moreover, every 10 g/m3 decrease of indoor AH was associated with the increase of 1.5 case of influenza (β = -1.5265; 95 % C.I. = -2.8085, -0.2445). This study was the first research to investigate the relationship between indoor absolute humidity and the severe complicated influenza case in Taiwan. In general, the finding in this studies is as similar as the previous studies, but the previous studies were focus on the weather station data, not the indoor environmental data. The mechanism of influenza transition and survival was better explained by absolute humidity because it was influenced by evaporation and droplet size. Although the period of this study was only 3 years, the longitudinal surveillance data were addressed in the future study to verify the accuracy and the finding of this study could supply the preliminary result to observe the outline of the difference between ambient and indoor environment. The preliminary result reveals that the effect of indoor AH on the outbreak of Influenza is greater than that of ambient AH. Indoor meteorological factors are critical to the preventive strategy of public health.
Abstract: Since 1997, avian influenza (AI) virus infections in poultry have taken on new significance, with increasing numbers of cases involving bird-to-human transmission and the resulting production of clinically severe and fatal human infections. Such human infections have been sporadic and are caused by H7N7 and H5N1 high-pathogenicity (HP) and H9N2 low-pathogenicity (LP) AI viruses in Europe and Asia. These infections have raised the level of concern by human health agencies for the potential reassortment of influenza virus genes and generation of the next human pandemic influenza A virus. The presence of endemic infections by H5N1 HPAI viruses in poultry in several Asian countries indicates that these viruses will continue to contaminate the environment and be an exposure risk with human transmission and infection. Furthermore, the reports of mammalian infections with H5N1 AI viruses and, in particular, mammal-to-mammal transmission in humans and tigers are unprecedented. However, the subsequent risk for generating a pandemic human strain is unknown. More international funding from both human and animal health agencies for diagnosis or detection and control of AI in Asia is needed. Additional funding for research is needed to understand why and how these AI viruses infect humans and what pandemic risks they pose.
Pub.: 29 Oct '05, Pinned: 28 Aug '17
Abstract: Almost all human infections by avian influenza viruses (AIVs) are transmitted from poultry. A systematic review was conducted to identify practices associated with human infections, their prevalence, and rationale. Observational studies were identified through database searches. Meta-analysis produced combined odds ratio estimates. The prevalence of practices and rationales for their adoptions were reported. Of the 48,217 records initially identified, 65 articles were included. Direct and indirect exposures to poultry were associated with infection for all investigated viral subtypes and settings. For the most frequently reported practices, association with infection seemed stronger in markets than households, for sick and dead than healthy poultry, and for H7N9 than H5N1. Practices were often described in general terms and their frequency and intensity of contact were not provided. The prevalence of practices was highly variable across studies, and no studies comprehensively explored reasons behind the adoption of practices. Combining epidemiological and targeted anthropological studies would increase the spectrum and detail of practices that could be investigated and should aim to provide insights into the rationale(s) for their existence. A better understanding of these rationales may help to design more realistic and acceptable preventive public health measures and messages.
Pub.: 28 Jul '17, Pinned: 28 Aug '17