Transmission Characteristics of Different Students during a School Outbreak of (H1N1) pdm09 Influenza in China, 2009

Many outbreaks of A(H1N1)pdm09 influenza have occurred in schools with a high population density. Containment of school outbreaks is predicted to help mitigate pandemic influenza. Understanding disease transmission characteristics within the school setting is critical to implementing effective control measures. Based on a school outbreak survey, we found almost all (93.7%) disease transmission occurred within a single grade, only 6.3% crossed grades. Transmissions originating from freshmen exhibited a star-shaped network; other grades exhibited branch- or line-shaped networks, indicating freshmen have higher activity and are more likely to cause infection. R0 for freshmen, calculated as 2.04, estimated as 2.76, was greater than for other grades (P < 0.01). Without intervention, the estimated number of cases was much greater when the outbreak was initiated by freshmen than by other grades. Furthermore, the estimated number of cases required to be under quarantine and isolation for freshmen was less than that of equivalent other grades. So we concluded that different grades have different transmission mode. Freshmen were the main facilitators of the spread of A(H1N1)pdm09 influenza during this school outbreak, so control measures (e.g. close contact isolation) priority used for freshmen would likely have effectively reduced spread of influenza in school settings.

[1]  Aravind Srinivasan,et al.  Modelling disease outbreaks in realistic urban social networks , 2004, Nature.

[2]  Yong Wang,et al.  Quarantine Methods and Prevention of Secondary Outbreak of Pandemic (H1N1) 2009 , 2010, Emerging infectious diseases.

[3]  Christl A. Donnelly,et al.  Transmission Dynamics, Border Entry Screening, and School Holidays during the 2009 Influenza A (H1N1) Pandemic, China , 2012, Emerging infectious diseases.

[4]  D. Swerdlow,et al.  Non-pharmaceutical interventions during an outbreak of 2009 pandemic influenza A (H1N1) virus infection at a large public university, April-May 2009. , 2011, Clinical infectious diseases : an official publication of the Infectious Diseases Society of America.

[5]  Seong-Ho Kang,et al.  Positive Rates of 2009 Novel Influenza A (H1N1) was High in School-Aged Individuals: Significance in Pandemic Control , 2012, Journal of Korean medical science.

[6]  P. Kelly,et al.  Transmissibility of 2009 pandemic influenza A(H1N1) in New Zealand: effective reproduction number and influence of age, ethnicity and importations. , 2010, Euro surveillance : bulletin Europeen sur les maladies transmissibles = European communicable disease bulletin.

[7]  J. Dushoff,et al.  Effects of School Closure on Incidence of Pandemic Influenza in Alberta, Canada , 2012 .

[8]  D. Cummings,et al.  Strategies for mitigating an influenza pandemic , 2006, Nature.

[9]  Li-ping Wang,et al.  American Journal of Epidemiology Original Contribution Distribution and Risk Factors of 2009 Pandemic Influenza a (h1n1) in Mainland China , 2022 .

[10]  M. Li,et al.  Global dynamics of a SEIR model with varying total population size. , 1999, Mathematical Biosciences.

[11]  Ellen Brooks-Pollock,et al.  Measured Dynamic Social Contact Patterns Explain the Spread of H1N1v Influenza , 2012, PLoS Comput. Biol..

[12]  M. Newman.  Spread of epidemic disease on networks. , 2002, Physical review. E, Statistical, nonlinear, and soft matter physics.

[13]  Shawn T. Brown,et al.  Simulating school closure strategies to mitigate an influenza epidemic. , 2010, Journal of public health management and practice : JPHMP.

[14]  Alessandro Vespignani,et al.  influenza A(H1N1): a Monte Carlo likelihood analysis based on , 2009 .

[15]  S. Blower,et al.  Theory versus Data: How to Calculate R0? , 2007, PloS one.

[16]  Kourosh Mozafari,et al.  Hepatitis disease diagnosis using a novel hybrid method based on support vector machine and simulated annealing (SVM-SA) , 2012, Comput. Methods Programs Biomed..

[17]  S. Washizuka,et al.  How the H1N1 influenza epidemic spread among university students in Japan: experience from Shinshu University. , 2012, American journal of infection control.

[18]  A. Kumar,et al.  Emergence of a Novel Swine-Origin Influenza A (H1N1) Virus in Humans , 2010 .

[19]  N. Ferguson,et al.  Role of social networks in shaping disease transmission during a community outbreak of 2009 H1N1 pandemic influenza , 2011, Proceedings of the National Academy of Sciences.

[20]  Beatrice Downie.  Effects of School Closure on Incidence of Pandemic Influenza in Alberta, Canada , 2012, Annals of Internal Medicine.

[21]  L. Finelli,et al.  Emergence of a novel swine-origin influenza A (H1N1) virus in humans. , 2009, The New England journal of medicine.

[22]  Vladimir Batagelj,et al.  Pajek - Analysis and Visualization of Large Networks , 2004, Graph Drawing Software.

[23]  Epidemiological and clinical characteristics of the outbreak of 2009 pandemic influenza A (H1N1) at a middle school in Luoyang, China. , 2012, Public health.

[24]  C. D. Gelatt,et al.  Optimization by Simulated Annealing , 1983, Science.

[25]  S. D. M. Ontañón,et al.  Transmisibilidad y gravedad de la pandemia de gripe A (H1N1) 2009 en España , 2011 .

[26]  B T Grenfell,et al.  Individual-based perspectives on R(0). , 2000, Journal of theoretical biology.

[27]  J. Medlock,et al.  Optimizing Influenza Vaccine Distribution , 2009, Science.

[28]  Simon Cauchemez,et al.  Competing Interests: Sc Received Consulting Fees from Sanofi Pasteur Msd on a Project on the Modelling of Varicella Zoster Virus. * , 2022 .

[29]  Sanyi Tang,et al.  Community-Based Measures for Mitigating the 2009 H1N1 Pandemic in China , 2010, PloS one.

[30]  S. Washizuka,et al.  Swine-Origin Influenza A Outbreak 2009 at Shinshu University, Japan , 2011, BMC public health.

[31]  C. Reed,et al.  Notes from the field: outbreak of 2009 pandemic influenza A (H1N1) virus at a large public university in Delaware, April-May 2009. , 2009, Clinical infectious diseases : an official publication of the Infectious Diseases Society of America.

[32]  Derek A T Cummings,et al.  Outbreak of 2009 pandemic influenza A (H1N1) at a New York City school. , 2009, The New England journal of medicine.

[33]  M. Newman,et al.  Network theory and SARS: predicting outbreak diversity , 2004, Journal of Theoretical Biology.

[34]  Transmission of 2009 pandemic influenza A (H1N1) at a Public University--Delaware, April-May 2009. , 2011, Clinical infectious diseases : an official publication of the Infectious Diseases Society of America.

[35]  Wu-Chun Cao,et al.  Dual Seasonal Patterns for Influenza, China , 2010, Emerging infectious diseases.

[36]  Western Pacific Region Global Influenza Surveillance and R System,et al.  Epidemiological and Virological Characteristics of Influenza in the Western Pacific Region of the World Health Organization, 2006–2010 , 2012, PloS one.

[37]  Masaya M. Saito,et al.  Extension and verification of the SEIR model on the 2009 influenza A (H1N1) pandemic in Japan. , 2013, Mathematical biosciences.

[38]  Sanyi Tang,et al.  Campus quarantine (Fengxiao) for curbing emergent infectious diseases: lessons from mitigating A/H1N1 in Xi'an, China. , 2012, Journal of theoretical biology.