title: Global Spatio-temporal Patterns of Influenza in the Post-pandemic Era.
abstract: We study the global spatio-temporal patterns of influenza dynamics. This is achieved by analysing and modelling weekly laboratory confirmed cases of influenza A and B from 138 countries between January 2006 and January 2015. The data were obtained from FluNet, the surveillance network compiled by the the World Health Organization. We report a pattern of skip-and-resurgence behavior between the years 2011 and 2013 for influenza H1N1pdm, the strain responsible for the 2009 pandemic, in Europe and Eastern Asia. In particular, the expected H1N1pdm epidemic outbreak in 2011/12 failed to occur (or "skipped") in many countries across the globe, although an outbreak occurred in the following year. We also report a pattern of well-synchronized wave of H1N1pdm in early 2011 in the Northern Hemisphere countries, and a pattern of replacement of strain H1N1pre by H1N1pdm between the 2009 and 2012 influenza seasons. Using both a statistical and a mechanistic mathematical model, and through fitting the data of 108 countries, we discuss the mechanisms that are likely to generate these events taking into account the role of multi-strain dynamics. A basic understanding of these patterns has important public health implications and scientific significance.
authors.affiliation: Department of Applied Mathematics, Hong Kong Polytechnic University, Hong Kong (SAR) China.
authors.forename: Daihai
authors.initials: D
authors.lastname: He
authors.affiliation: Department of Mathematical Sciences, Worcester Polytechnic Institute, 100 Institute Road Worcester, MA 01609, United States.
authors.forename: Roger
authors.initials: R
authors.lastname: Lui
authors.affiliation: School of Public Health, Li Ka Shing Faculty of Medicine, University of Hong Kong, Hong Kong (SAR) China.
authors.forename: Lin
authors.initials: L
authors.lastname: Wang
authors.affiliation: Department of Electronic and Information Engineering, Hong Kong Polytechnic University Hong Kong (SAR) China.
authors.forename: Chi Kong
authors.initials: CK
authors.lastname: Tse
authors.affiliation: School of Nursing, Hong Kong Polytechnic University, Hong Kong (SAR) China.
authors.forename: Lin
authors.initials: L
authors.lastname: Yang
authors.affiliation: 1] School of Mathematical and Geospatial Sciences, RMIT University, Melbourne, 3000, Australia [2] Department of Zoology, Biomathematics Unit, Tel Aviv University, Ramat Aviv, Israel.
authors.forename: Lewi
authors.initials: L
authors.lastname: Stone
mesh_terms: D006801:Humans; D053118:Influenza A Virus, H1N1 Subtype; D053122:Influenza A Virus, H3N2 Subtype; D007251:Influenza, Human / Q000453:epidemiology* / Q000821:virology; D015233:Models, Statistical; D058873:Pandemics; D012621:Seasons