(Geneva/Vienna, 03-01-2017) Up to 650 000 deaths annually are associated with respiratory diseases from seasonal influenza, according to new estimates by the United States Centers for Disease Control and Prevention (US-CDC), the World Health Organization and global health partners, including MedUni Vienna.
This marks an increase on the previous global estimate of 250 000 – 500 000, which dates from over ten years ago and covered all influenza-related deaths, including cardiovascular disease or diabetes. The new figures of 290 000 – 650 000 deaths are based on more recent data from a larger, more diverse group of countries, including lower middle income countries, and exclude deaths from non-respiratory diseases.
“These figures indicate the high burden of influenza and its substantial social and economic cost to the world,” said Peter Salama, Executive Director of WHO’s Health Emergencies Programme. “They highlight the importance of influenza prevention for seasonal epidemics, as well as preparedness for pandemics.”
The recently in The Lancet on Thursday (14 December) published study is conducted by the United States Centers for Disease Control and Prevention (US-CDC) and estimates the global influenza respiratory mortality.
Monika Redlberger-Fritz of the Austrian National Influenza Reference Laboratory at the Medical University of Vienna's Center for Virology (Head: Theresia Popow-Kraupp) in collaboration with Michael Kundi from MedUni Vienna's Center for Public Health contributed the Austrain data to this study. The extrapolated number of annual influenza-associated deaths in Austria over a 15-year period is based on data from the Diagnostic Influenza Network Austria (DINÖ, www.influenza.at), which is operated by the National Influenza Reference Laboratory at the Center for Virology to monitor the annual activity of influenza viruses in Austria.
The elderly and people from poorer regions particularly affected
According to US-CDC, most deaths occur among people aged over 75 years, and in the world’s poorest regions. Sub-Saharan Africa accounts for the world’s greatest flu mortality risk, followed closely by the Eastern Mediterranean and Southeast Asia.
“All countries, rich and poor, large and small, must work together to control influenza outbreaks before the arrival of the next pandemic. This includes building capacity to detect and respond to outbreaks, and strengthening health systems to improve the health of the most vulnerable and those most at risk,” said Peter Salama.
Nearly all deaths among children under five with influenza-related lower respiratory tract infections occur in developing countries, but the effects of seasonal influenza epidemics on the world’s poorest are not fully known.
WHO is working with partners to assess the global influenza burden of disease by providing guidance and expertise to Member States to measure the influenza disease burden and its economic consequences.
Further surveillance and laboratory studies of other diseases such as cardiovascular disease, which can be influenza-related, are expected to yield substantially higher estimates over the next few years.
Members of healthcare professions a high-risk group
WHO encourages countries to prioritize influenza prevention and produce national estimates to inform prevention policies. Annual influenza vaccination is recommended to prevent disease and complications from influenza infection. Vaccination is especially important for people at higher risk of serious influenza complications and death, and for health workers.
Seasonal influenza is an acute viral infection that spreads easily from person to person and circulates worldwide. Most people recover within a week without requiring medical attention. Common respiratory diseases related to seasonal influenza that can cause death include pneumonia and bronchitis.
The study authors note that these new estimates are limited to flu-associated respiratory deaths and therefore may underestimate the true global impact of seasonal influenza. Influenza infection can create or exacerbate other health factors which are then listed as the cause of death on death certificates, for example cardiovascular disease, diabetes, or related complications. Additional research to estimate non-respiratory causes of flu-associated deaths are ongoing.
Service: The Lancet
Estimates of global seasonal influenza-associated respiratory mortality: a modelling study
A Danielle Iuliano, Katherine M Roguski, Howard H Chang, David J Muscatello, Rakhee Palekar, Stefano Tempia, Cheryl Cohen, Jon Michael Gran, Dena Schanzer, Benjamin J Cowling, Peng Wu, Jan Kyncl, Li Wei Ang, Minah Park, Monika Redlberger-Fritz, Hongjie Yu, Laura Espenhain, Anand Krishnan, Gideon Emukule, Liselotte van Asten, Susana Pereira da Silva, Suchunya Aungkulanon, Udo Buchholz, Marc-Alain Widdowson, Joseph S Bresee, for the Global Seasonal Influenza-associated Mortality Collaborator Network; Published Online December 13, 2017
Online commentary: dx.doi.org/10.1016/S0140-6736(17)33292-0