Journal of Geo-information Science >
Characterization of the Global Spatio-temporal Transmission of the 2009 Pandemic H1N1 Influenza
Received date: 2012-11-19
Revised date: 2012-11-21
Online published: 2012-12-25
In March of 2009, a novel swine-origin influenza A(H1N1) virus was first discovered in Mexico and quickly spread to over 200 countries in less than two years. However, limited research has been conducted on the characterization of the global spatio-temporal transmission of the pandemic. Applying Ripley's K function based on the spherical distances, we analyzed spatial pattern of the outbreaks of the H1N1 pandemic from March 15, 2009 to June 9, 2009. Compared with other type A influenza occurred during 2000-2008, the 2009 H1N1 influenza showed generally similar temporal trend, but marked difference when we broke down the outbreak data of each country along the latitude. To look into the differences, we further associated the number of weekly cases of the H1N1 influenza with national arrivals through customs. Results show that the 2009 H1N1 influenza in early period was spatially clustered. The maximum value of the function L was identical to that of the 65 global cities, within which 79 percent of the outbreaks were distributed within a radius of 600 km. In addition, the correlation coefficients show that the highest positive correlation (r=0.7,p=.002) between national arrivals and weekly influenza cases lied in the 19th week. These findings suggest that global cities are the key nodes of the network which disseminates international travels, hence the viruses in the early period of the pandemic. It was found that the seasonal environmental factors also have impact on the influenza pandemic through applying time series analysis. Unexpectedly, some countries in the northern temperate zone reported more confirmed human cases in June and July when was thought not to be suitable for the transmission of the influenza. In the meantime, the winter peaks of cases for the countries that lie to the north of the tropic of cancer are clustered around the period between the 45th week and the 48th week, which is earlier than the common type A influenza season. It might partially due to the lack of immunity among the population against the pandemic A(H1N1)2009 virus.
JIANG Zhi-Ben, BAI Jian-Jun, CA Dun, LI Rui-Yun, JIN Shen-Yu, XU Bing . Characterization of the Global Spatio-temporal Transmission of the 2009 Pandemic H1N1 Influenza[J]. Journal of Geo-information Science, 2012 , 14(6) : 794 -799 . DOI: 10.3724/SP.J.1047.2012.00794
[1] World Health Organizations (WHO). Influenza (Seasonal) [R]. http://www.who.int/mediacentre/factsheets/fs211/en/index.html.
[2] Tellier R. Aerosol transmission of influenza A virus: A review of new studies[J]. J R Soc Interface, 2009,6:783-790.
[3] Lowen A C, Steel J, Mubareka S, et al. High temperature (30 degrees C) blocks aerosol but not contact transmission of influenza virus[J]. J Virol, 2008,82(11):5650-5652.
[4] Lowen A C, Mubareka S, Steel J, et al. Influenza virus transmission is dependent on relative humidity and temperature[J]. PLoS Pathog, 2007,3(10):1470-1476.
[5] Shaman J and Kohn M. Absolute humidity modulates influenza survival, transmission, and seasonality[J]. P Natl Acad Sci USA, 2009,106(9):3243-3248.
[6] Lowen A and Palese P. Transmission of influenza virus in temperate zones is predominantly by aerosol, in the tropics by contact: A hypothesis[J]. PLoS Curr, 2009,1:RRN1002.
[7] Flahault A, Viboud C, Pakdaman K, et al. Association of influenza epidemics in France and the USA with global climate variability[J]. International Congress Series, 2004,1263:73-77.
[8] Viboud C, Pakdaman K, Boelle P Y, et al. Association of influenza epidemics with global climate variability[J]. Eur J Epidemiol, 2004,19(11):1055-1059.
[9] Saker L, Lee K, Cannito B, et al. Globalization and infectious diseases: A review of the linkages[M]. Social, Economic and Behavioural Research, WHO, 2004.
[10] United Nations Population Fund (UNFPA). Linking population, poverty and development [R]. http://www.unfpa.org/pds/migration.html.
[11] Grais R F, Ellis J H, and Glass G E. Assessing the impact of airline travel on the geographic spread of pandemic influenza[J]. Eur J Epidemiol, 2003, 18(11):1065-1072.
[12] Cooper B S, Pitman R J, Edmunds W J, et al. Delaying the international spread of pandemic influenza[J]. PLoS Med, 2006, 3(6):845-855.
[13] World Health Organizations (WHO). Influenza A(H1N1)-update 5 [R]. http://www.who.int/csr/don/2009_04_29/en/index.html.
[14] World Health Organizations (WHO).Pandemic (H1N1) 2009-update 99 [R]. http://www.who.int/csr/don/2010_05_07/en/index.html.
[15] Philip M D. Encyclopedia of Environmetrics[M]. USA: John Wiley & Sons, 2002, 1796-1803.
[16] Liang L, Xu B, Chen Y L, et al. Combining spatial-temporal and phylogenetic analysis approaches for improved understanding on global H5N1 transmission[J]. PLoS ONE, 2010, 5(10): e13575.
[17] Mike H, Samantba K, Andres M P. The A. T. Kearney Global Cities Index 2010. USA: A. T. Kearney, 2011, 1-15.
[18] Rizzo C, Rota M C, Bella A, et al. Cross-reactive antibody responses to the 2009 A/H1N1v influenza virus in the Italian population in the pre-pandemic period[J]. Vaccine, 2010, 28(20): 3558-3562.
[19] Hancock K, Veguilla V, Lu X, et al. Cross-reactive antibody responses to the 2009 pandemic H1N1 influenza virus[J]. N Engl J Med, 2009, 361(20):1945-1952.
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