Ka Chun Chong1, Tsz Cheung Lee2, Seweryn Bialasiewicz3, Jian Chen4, David W Smith5, Wisely S C Choy2, Mel Krajden6, Hamid Jalal7, Lance Jennings8, Burmaa Alexander9, Hong Kai Lee10, Pieter Fraaij11, Avram Levy5, Apple C M Yeung12, Sarah Tozer3, Steven Y F Lau1, Katherine M Jia1, Julian W T Tang13, David S C Hui14, Paul K S Chan15. 1. Jockey Club School of Public Health and Primary Care, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong Special Administrative Region, China. 2. Hong Kong Observatory, Government of The Hong Kong Special Administrative Region, Hong Kong Special Administrative Region, China. 3. Child Health Research Centre, The University of Queensland, Brisbane, Australia; Centre for Children's Health Research, Brisbane, Australia. 4. Shanghai Municipal Center for Disease Control and Prevention, Shanghai, China. 5. Faculty of Medicine and Health Sciences, University of Western Australia, Perth, Australia; Department of Microbiology, PathWest QEII Medical Centre, Perth, Australia. 6. British Columbia Centre for Disease Prevention and Control, Vancouver, BC, Canada. 7. Clinical Microbiology and Public Health Laboratory, Health Protection Agency, Addenbrooke's Hospital, Cambridge, United Kingdom. 8. Pathology Department, University of Otago, Christchurch, New Zealand. 9. National Influenza Center, National Center of Communicable Diseases, Ministry of Health, Mongolia. 10. Department of Laboratory Medicine, National University Hospital, Singapore. 11. Erasmus Medical Centre, Rotterdam, the Netherlands. 12. Department of Microbiology, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong Special Administrative Region, China. 13. University Hospitals Leicester, University of Leicester, Leicester, United Kingdom. 14. Department of Medicine and Therapeutics, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong Special Administrative Region, China; Stanley Ho Centre for Emerging Infectious Diseases, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong Special Administrative Region, China. 15. Department of Microbiology, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong Special Administrative Region, China; Stanley Ho Centre for Emerging Infectious Diseases, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong Special Administrative Region, China. Electronic address: paulkschan@cuhk.edu.hk.
Abstract
OBJECTIVE: To elucidate the effects of meteorological variations on the activity of influenza A and B in 11 sites across different climate regions. METHODS: Daily numbers of laboratory-confirmed influenza A and B cases from 2011-2015 were collected from study sites where the corresponding daily mean temperature, relative humidity, wind speed and daily precipitation amount were used for boosted regression trees analysis on the marginal associations and the interaction effects. RESULTS: Cold temperature was a major determinant that favored both influenza A and B in temperate and subtropical sites. Temperature-to-influenza A, but not influenza B, exhibited a U-shape association in subtropical and tropical sites. High relative humidity was also associated with influenza activities but was less consistent with influenza B activity. Compared with relative humidity, absolute humidity had a stronger association - it was negatively associated with influenza B activity in temperate zones, but was positively associated with both influenza A and B in subtropical and tropical zones. CONCLUSION: The association between meteorological factors and with influenza activity is virus type specific and climate dependent. The heavy influence of temperature on influenza activity across climate zones implies that global warming is likely to have an impact on the influenza burden.
OBJECTIVE: To elucidate the effects of meteorological variations on the activity of influenza A and B in 11 sites across different climate regions. METHODS: Daily numbers of laboratory-confirmed influenza A and B cases from 2011-2015 were collected from study sites where the corresponding daily mean temperature, relative humidity, wind speed and daily precipitation amount were used for boosted regression trees analysis on the marginal associations and the interaction effects. RESULTS: Cold temperature was a major determinant that favored both influenza A and B in temperate and subtropical sites. Temperature-to-influenza A, but not influenza B, exhibited a U-shape association in subtropical and tropical sites. High relative humidity was also associated with influenza activities but was less consistent with influenza B activity. Compared with relative humidity, absolute humidity had a stronger association - it was negatively associated with influenza B activity in temperate zones, but was positively associated with both influenza A and B in subtropical and tropical zones. CONCLUSION: The association between meteorological factors and with influenza activity is virus type specific and climate dependent. The heavy influence of temperature on influenza activity across climate zones implies that global warming is likely to have an impact on the influenza burden.
Authors: G L Nichols; E L Gillingham; H L Macintyre; S Vardoulakis; S Hajat; C E Sarran; D Amankwaah; R Phalkey Journal: BMC Infect Dis Date: 2021-10-26 Impact factor: 3.090