Featured Research

from universities, journals, and other organizations

Flu Mortality Formula Is Potentially Misleading, Say Scientists

Date:
July 16, 2009
Source:
Imperial College London
Summary:
A standard calculation used in forecasting potential numbers of deaths during the swine flu pandemic risks misleading health-care planners by being open to both over- and under-estimation of the true figures, according to experts.

A standard calculation used in forecasting potential numbers of deaths during the swine flu pandemic risks misleading healthcare planners by being open to both over- and under-estimation of the true figures, say the authors of new research published in the British Medical Journal.

The proportion of people who die due to infection during an influenza outbreak - known as the case fatality ratio - is calculated by dividing the number of deaths by the total number of cases in the same time period. Early data from the current swine flu pandemic suggested that the new influenza A (H1N1) virus causes mild disease, with case fatality ratios of around 0.5%, or 5 deaths per 1000 people infected.

However, the researchers from the MRC Centre for Outbreak Analysis & Modelling at Imperial College London, say this ratio may not be accurate.

They highlight three reasons for the inaccuracy. Firstly, that the total number of deaths during this pandemic is being underestimated because the cause of death is not correctly attributed to swine flu (e.g. influenza can temporarily increase the risk of vascular events, such as heart attacks).

Secondly that as the pandemic progresses, the total number of cases tends towards underestimation, as people presenting with milder symptoms may not be tested or visit a doctor at all, leaving only the most severe to be reported.

Thirdly, that the 'snapshot' calculation does not take account of the time delay between infection and death, thus leading to the false impression that the infection is actually becoming more severe as the pandemic progresses.

Dr Tini Garske, lead author of the study from the MRC Centre for Outbreak Analysis & Modelling at Imperial College London, said:

"Accurately predicting the severity of this swine flu pandemic is a very tricky business, and our research shows that this can only be achieved if data is collected according to well designed study protocols and analysed in a more sophisticated way than is frequently being performed at present.

"If we fail to get an accurate prediction of severity, we will not be providing healthcare planners, doctors and nurses, with the information that they need to ensure they are best prepared to fight the pandemic as we head into the flu season this autumn.

The research was funded by a Medical Research Council UK Centre grant.


Story Source:

The above story is based on materials provided by Imperial College London. Note: Materials may be edited for content and length.


Cite This Page:

Imperial College London. "Flu Mortality Formula Is Potentially Misleading, Say Scientists." ScienceDaily. ScienceDaily, 16 July 2009. <www.sciencedaily.com/releases/2009/07/090714191848.htm>.
Imperial College London. (2009, July 16). Flu Mortality Formula Is Potentially Misleading, Say Scientists. ScienceDaily. Retrieved September 18, 2014 from www.sciencedaily.com/releases/2009/07/090714191848.htm
Imperial College London. "Flu Mortality Formula Is Potentially Misleading, Say Scientists." ScienceDaily. www.sciencedaily.com/releases/2009/07/090714191848.htm (accessed September 18, 2014).

Share This



More Health & Medicine News

Thursday, September 18, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Artificial Sweetener Could Promote Diabetes

Artificial Sweetener Could Promote Diabetes

Newsy (Sep. 17, 2014) Doctors once thought artificial sweeteners lacked the health risks of sugar, but a new study says they can impact blood sugar levels the same way. Video provided by Newsy
Powered by NewsLook.com
Ebola Vaccine Trial Gets Underway at Oxford University

Ebola Vaccine Trial Gets Underway at Oxford University

AFP (Sep. 17, 2014) A healthy British volunteer is to become the first person to receive a new vaccine for the Ebola virus after US President Barack Obama called for action against the epidemic and warned it was "spiralling out of control." Duration: 01:02 Video provided by AFP
Powered by NewsLook.com
Obesity Rates Steady Even As Americans' Waistlines Expand

Obesity Rates Steady Even As Americans' Waistlines Expand

Newsy (Sep. 17, 2014) Researchers are puzzled as to why obesity rates remain relatively stable as average waistlines continue to expand. Video provided by Newsy
Powered by NewsLook.com
President To Send 3,000 Military Personnel To Fight Ebola

President To Send 3,000 Military Personnel To Fight Ebola

Newsy (Sep. 16, 2014) President Obama is expected to send 3,000 troops to West Africa as part of the effort to contain Ebola's spread. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins