tetano
Editor, Senior Moderator
Sci Total Environ. 2019 Oct 31;703:134727. doi: 10.1016/j.scitotenv.2019.134727. [Epub ahead of print] [h=1]Latitudes mediate the association between influenza activity and meteorological factors: A nationwide modelling analysis in 45 Japanese prefectures from 2000 to 2018.[/h]
Chong KC[SUP]1[/SUP], Liang J[SUP]2[/SUP], Jia KM[SUP]3[/SUP], Kobayashi N[SUP]4[/SUP], Wang MH[SUP]5[/SUP], Wei L[SUP]2[/SUP], Lau SYF[SUP]6[/SUP], Sumi A[SUP]7[/SUP].
[h=3]Author information[/h] 1 JC School of Public Health and Primary Care, The Chinese University of Hong Kong, Hong Kong, China; Clinical Trials and Biostatistics Laboratory, Shenzhen Research Institute, The Chinese University of Hong Kong, China. Electronic address: marc@cuhk.edu.hk. 2 JC School of Public Health and Primary Care, The Chinese University of Hong Kong, Hong Kong, China. 3 JC School of Public Health and Primary Care, The Chinese University of Hong Kong, Hong Kong, China. Electronic address: 1155078733@link.cuhk.edu.hk. 4 Department of Hygiene, Sapporo Medical University School of Medicine, Sapporo, Japan. Electronic address: nkobayas@sapmed.ac.jp. 5 JC School of Public Health and Primary Care, The Chinese University of Hong Kong, Hong Kong, China; Clinical Trials and Biostatistics Laboratory, Shenzhen Research Institute, The Chinese University of Hong Kong, China. Electronic address: maggiew@cuhk.edu.hk. 6 JC School of Public Health and Primary Care, The Chinese University of Hong Kong, Hong Kong, China. Electronic address: stevenlau@cuhk.edu.hk. 7 Department of Hygiene, Sapporo Medical University School of Medicine, Sapporo, Japan. Electronic address: sumi@sapmed.ac.jp.
[h=3]Abstract[/h] [h=4]BACKGROUND:[/h] Cold and dry conditions were well-documented as a major determinant of influenza seasonality in temperate countries but the association may not be consistent when the climate in temperate areas is closer to that in sub-tropical areas. We hypothesized latitudes may mediate the association between influenza activity and meteorological factors in 45 Japanese prefectures.
[h=4]METHODS:[/h] We used the weekly incidence of influenza-like illness of 45 prefectures from 2000 to 2018 as a proxy for influenza activity in Japan, a temperate country lying off the east coast of Asia. A combination of generalized additive model and distributed lag nonlinear model was adopted to investigate the associations between meteorological factors (average temperature, relative humidity, total rainfall, and actual vapour pressure, a proxy for absolute humidity) and the influenza incidence. Kendall's tau b (τ) and Spearman correlation coefficient (r[SUB]s[/SUB]) between latitude and the adjusted relative risk (ARR) of each meteorological factor were also assessed.
[h=4]RESULTS:[/h] A higher vapour pressure was significantly associated with a lower influenza risk but the ARR strongly weakened along with a lower latitude (τ = -0.23, p-value = 0.02; r[SUB]s[/SUB] = -0.33, p-value = 0.03). Lower temperature and lower relatively humidity were significantly associated with higher influenza risks in over 65% and around 40% of the prefectures respectively but the strength and significance of the correlations between their ARRs and latitude were weaker than that from vapour pressure.
[h=4]CONCLUSION:[/h] Even though the range of latitudes in Japan is small (26?N-43?N), the relationships between meteorological factors and influenza activity were mediated by the latitude. Our study echoed absolute humidity played a more important role in relating influenza risk, but we on the other hand showed its effect on influenza activity could be hampered in a low-latitude temperate region, which have a warmer climate. These findings thus offer a high-resolution characterization of the role of meteorological factors on influenza seasonality.
Copyright ? 2019 Elsevier B.V. All rights reserved.
[h=4]KEYWORDS:[/h] Humidity; Influenza; Japan; Latitude; Temperature
PMID: 31731153 DOI: 10.1016/j.scitotenv.2019.134727
Chong KC[SUP]1[/SUP], Liang J[SUP]2[/SUP], Jia KM[SUP]3[/SUP], Kobayashi N[SUP]4[/SUP], Wang MH[SUP]5[/SUP], Wei L[SUP]2[/SUP], Lau SYF[SUP]6[/SUP], Sumi A[SUP]7[/SUP].
[h=3]Author information[/h] 1 JC School of Public Health and Primary Care, The Chinese University of Hong Kong, Hong Kong, China; Clinical Trials and Biostatistics Laboratory, Shenzhen Research Institute, The Chinese University of Hong Kong, China. Electronic address: marc@cuhk.edu.hk. 2 JC School of Public Health and Primary Care, The Chinese University of Hong Kong, Hong Kong, China. 3 JC School of Public Health and Primary Care, The Chinese University of Hong Kong, Hong Kong, China. Electronic address: 1155078733@link.cuhk.edu.hk. 4 Department of Hygiene, Sapporo Medical University School of Medicine, Sapporo, Japan. Electronic address: nkobayas@sapmed.ac.jp. 5 JC School of Public Health and Primary Care, The Chinese University of Hong Kong, Hong Kong, China; Clinical Trials and Biostatistics Laboratory, Shenzhen Research Institute, The Chinese University of Hong Kong, China. Electronic address: maggiew@cuhk.edu.hk. 6 JC School of Public Health and Primary Care, The Chinese University of Hong Kong, Hong Kong, China. Electronic address: stevenlau@cuhk.edu.hk. 7 Department of Hygiene, Sapporo Medical University School of Medicine, Sapporo, Japan. Electronic address: sumi@sapmed.ac.jp.
[h=3]Abstract[/h] [h=4]BACKGROUND:[/h] Cold and dry conditions were well-documented as a major determinant of influenza seasonality in temperate countries but the association may not be consistent when the climate in temperate areas is closer to that in sub-tropical areas. We hypothesized latitudes may mediate the association between influenza activity and meteorological factors in 45 Japanese prefectures.
[h=4]METHODS:[/h] We used the weekly incidence of influenza-like illness of 45 prefectures from 2000 to 2018 as a proxy for influenza activity in Japan, a temperate country lying off the east coast of Asia. A combination of generalized additive model and distributed lag nonlinear model was adopted to investigate the associations between meteorological factors (average temperature, relative humidity, total rainfall, and actual vapour pressure, a proxy for absolute humidity) and the influenza incidence. Kendall's tau b (τ) and Spearman correlation coefficient (r[SUB]s[/SUB]) between latitude and the adjusted relative risk (ARR) of each meteorological factor were also assessed.
[h=4]RESULTS:[/h] A higher vapour pressure was significantly associated with a lower influenza risk but the ARR strongly weakened along with a lower latitude (τ = -0.23, p-value = 0.02; r[SUB]s[/SUB] = -0.33, p-value = 0.03). Lower temperature and lower relatively humidity were significantly associated with higher influenza risks in over 65% and around 40% of the prefectures respectively but the strength and significance of the correlations between their ARRs and latitude were weaker than that from vapour pressure.
[h=4]CONCLUSION:[/h] Even though the range of latitudes in Japan is small (26?N-43?N), the relationships between meteorological factors and influenza activity were mediated by the latitude. Our study echoed absolute humidity played a more important role in relating influenza risk, but we on the other hand showed its effect on influenza activity could be hampered in a low-latitude temperate region, which have a warmer climate. These findings thus offer a high-resolution characterization of the role of meteorological factors on influenza seasonality.
Copyright ? 2019 Elsevier B.V. All rights reserved.
[h=4]KEYWORDS:[/h] Humidity; Influenza; Japan; Latitude; Temperature
PMID: 31731153 DOI: 10.1016/j.scitotenv.2019.134727