Influenza Humans Commons^™

Global Mortality Impact Of The 1957–1959 Influenza Pandemic, Cecile Viboud, Lone Simonsen, Rodrigo Fuentes, Jose Flores, Mark A. Miller, Gerardo Chowell

Global Health Faculty Publications

Background. Quantitative estimates of the global burden of the 1957 influenza pandemic are lacking. Here we fill this gap by modeling historical mortality statistics.

Methods. We used annual rates of age- and cause-specific deaths to estimate pandemic-related mortality in excess of background levels in 39 countries in Europe, the Asia-Pacific region, and the Americas. We modeled the relationship between excess mortality and development indicators to extrapolate the global burden of the pandemic.

Results. The pandemic-associated excess respiratory mortality rate was 1.9/10 000 population (95% confidence interval [CI], 1.2–2.6 cases/10 000 population) on average during 1957–1959. Excess mortality rates varied 70-fold …

A Global Map Of Hemispheric Influenza Vaccine Recommendations Based On Local Patterns Of Viral Circulation, Wladimir J. Alonso, Christine Yu, Cecile Viboud, Stephanie A. Richard, Cynthia Schuck-Paim, Lone Simonsen, Wyller A. Mello, Mark A. Miller

Global Health Faculty Publications

Both the Northern and the Southern Hemisphere annual WHO influenza vaccine recommendations are designed to ensure vaccine delivery before the winter-time peak of viral circulation in each hemisphere. However, influenza seasonal patterns are highly diverse in tropical countries and may be out of phase with the WHO recommendations for their respective hemisphere. We modelled the peak timing of influenza activity for 125 countries using laboratory-based surveillance data from the WHO’s FLUNET database and compared it with the influenza hemispheric recommendations in place. Influenza vaccine recommendations for respectively 25% and 39% of the Northern and Southern Hemisphere countries were out of …

Detecting Signals Of Seasonal Influenza Severity Through Age Dynamics, Elizabeth C Lee, Cécile Viboud, Lone Simonsen, Farid Khan, Shweta Bansal

Global Health Faculty Publications

BACKGROUND: Measures of population-level influenza severity are important for public health planning, but estimates are often based on case-fatality and case-hospitalization risks, which require multiple data sources, are prone to surveillance biases, and are typically unavailable in the early stages of an outbreak. To address the limitations of traditional indicators, we propose a novel severity index based on influenza age dynamics estimated from routine physician diagnosis data that can be used retrospectively and for early warning.

METHODS: We developed a quantitative 'ground truth' severity benchmark that synthesizes multiple traditional severity indicators from publicly available influenza surveillance data in the United …

Death Patterns During The 1918 Influenza Pandemic In Chile, Gerardo Chowell, Lone Simonsen, Jose Flores, Mark A. Miller, Cecile G. Viboud

Global Health Faculty Publications

Scarce information about the epidemiology of historical influenza pandemics in South America prevents complete understanding of pandemic patterns throughout the continent and across different climatic zones. To fill gaps with regard to spatiotemporal patterns of deaths associated with the 1918 influenza pandemic in Chile, we reviewed archival records. We found evidence that multiple pandemic waves at various times of the year and of varying intensities occurred during 1918-1921 and that influenza-related excess deaths peaked during July-August 1919. Pandemic-associated mortality rates were elevated for all age groups, including for adults >50 years of age; elevation from baseline was highest for young …

The Association Of Meningococcal Disease With Influenza In The United States, 1989-2009, Jessica Hartman Jacobs, Cecile Viboud, Eric Tchetgen Tchetgen, Joel Schwartz, Claudia Steiner, Lone Simonsen, Marc Lipsitch

Global Health Faculty Publications

Importance and Objective

Prior influenza infection is a risk factor for invasive meningococcal disease. Quantifying the fraction of meningococcal disease attributable to influenza could improve understanding of viral-bacterial interaction and indicate additional health benefits to influenza immunization.

Design, Setting and Participants

A time series analysis of the association of influenza and meningococcal disease using hospitalizations in 9 states from 1989–2009 included in the State Inpatient Databases from the Agency for Healthcare Research and Quality and the proportion of positive influenza tests by subtype reported to the Centers for Disease Control. The model accounts for the autocorrelation of meningococcal disease and …

Spatial Transmission Of 2009 Pandemic Influenza In The Us, Julia R. Gog, Sebastien Ballesteros, Cecile G. Viboud, Lone Simonsen, Ottar N. Bjornstad, Jeffrey Shaman, Dennis L. Chao, Farid Khan, Bryan T. Grenfell

Global Health Faculty Publications

The 2009 H1N1 influenza pandemic provides a unique opportunity for detailed examination of the spatial dynamics of an emerging pathogen. In the US, the pandemic was characterized by substantial geographical heterogeneity: the 2009 spring wave was limited mainly to northeastern cities while the larger fall wave affected the whole country. Here we use finely resolved spatial and temporal influenza disease data based on electronic medical claims to explore the spread of the fall pandemic wave across 271 US cities and associated suburban areas. We document a clear spatial pattern in the timing of onset of the fall wave, starting in …

Global Mortality Estimates For The 2009 Influenza Pandemic From The Glamor Project: A Modeling Study, Lone Simonsen, Peter Spreeuwenberg, Roger Lustig, Robert J. Taylor, Douglas M. Fleming, Madelon Kroneman, Maria D. Van Kerkhove, Anthony D. Mounts, W. John Paget

Global Health Faculty Publications

Background

Assessing the mortality impact of the 2009 influenza A H1N1 virus (H1N1pdm09) is essential for optimizing public health responses to future pandemics. The World Health Organization reported 18,631 laboratory-confirmed pandemic deaths, but the total pandemic mortality burden was substantially higher. We estimated the 2009 pandemic mortality burden through statistical modeling of mortality data from multiple countries.

Methods and Findings

We obtained weekly virology and underlying cause-of-death mortality time series for 2005–2009 for 20 countries covering ~35% of the world population. We applied a multivariate linear regression model to estimate pandemic respiratory mortality in each collaborating country. We then used …

The Influence Of Climatic Conditions On The Transmission Dynamics Of The 2009 A/H1n1 Influenza Pandemic In Chile, Gerardo Chowell, Sherry Towers, Cecile Viboud, Rodrigo Fuentes, Viviana Sotomayor, Lone Simonsen, Mark A. Miller, Mauricio Lima, Claudia Villarroel, Monica Chiu, Jose E. Villarroel, Andrea Olea

Global Health Faculty Publications

No abstract provided.

Mortality Burden Of The 2009 A/H1n1 Influenza Pandemic In France: Comparison To Seasonal Influenza And The A/H3n2 Pandemic, Magali Lematire, Fabrice Carrat, Gregoire Rey, Mark A. Miller, Lone Simonsen, Cecile Viboud

Global Health Faculty Publications

Background

The mortality burden of the 2009 A/H1N1 pandemic remains unclear in many countries due to delays in reporting of death statistics. We estimate the age- and cause-specific excess mortality impact of the pandemic in France, relative to that of other countries and past epidemic and pandemic seasons.

Methods

We applied Serfling and Poisson excess mortality approaches to model weekly age- and cause-specific mortality rates from June 1969 through May 2010 in France. Indicators of influenza activity, time trends, and seasonal terms were included in the models. We also reviewed the literature for country-specific estimates of 2009 pandemic excess mortality …