Featured Research

from universities, journals, and other organizations

Major Mid-century Influenza Epidemics Caused By Novel Hybrid Viruses

Date:
March 3, 2008
Source:
Public Library of Science
Summary:
Reassortment of the influenza A virus occurs frequently throughout its evolutionary history, according to a new study in PLoS Pathogens. The researchers found that the severe influenza epidemics of 1947 and 1951 were caused by genetic reassortment events in which two human influenza viruses of the same H1N1 strain exchanged genetic material, producing a new hybrid virus in both cases.

This transmission electron micrograph (TEM) of an ultra-thin specimen revealed some of the ultrastructural morphologic features seen in 1918 influenza virus virions.
Credit: Cynthia Goldsmith

Reassortment of the influenza A virus occurs frequently throughout its evolutionary history. Researchers at Pennsylvania State University and the National Institute of Health used an evolutionary analysis of influenza viruses sampled from 1918 -- 2005 to investigate the influenza viruses that cause seasonal epidemics in humans, particularly those where mortality was unusually high.

Specifically, the researchers found that the severe influenza epidemics of 1947 and 1951 were caused by genetic reassortment events in which two human influenza viruses of the same H1N1 strain exchanged genetic material, producing a new hybrid virus in both cases.

It has been a mystery why unusually severe epidemics of influenza occur from time to time, such as in 1947 and 1951, when illness and mortality rates exceeded standard epidemic levels. The standard model of human influenza virus evolution holds that major influenza pandemics, the largest of which occurred in 1918, are caused by reassortment between human and avian influenza viruses. But seasonal influenza epidemics, which occur each winter in the United States, do not involve the reassortment of genetic material.

These new findings suggest that the evolution of seasonal influenza is more complex than previously thought, and that multiple forms of the same strain co-circulate and re-assort within a single population, rapidly generating genetically novel viruses with the potential to ignite major epidemics. It is therefore critical that intensive surveillance is undertaken to capture the full extent of influenza genetic diversity that co-circulates at a given time, particularly as an aid to vaccine design.

Journal reference: Nelson MI, Viboud C, Simonsen L, Bennett RT, Griesemer SB, et al. (2008) Multiple Reassortment Events in the Evolutionary History of H1N1 Influenza A Virus Since 1918. PLoS Pathog 4(2): e1000012. doi:10.1371/journal.ppat.1000012 http://www.plospathogens.org/doi/ppat.1000012


Story Source:

The above story is based on materials provided by Public Library of Science. Note: Materials may be edited for content and length.


Cite This Page:

Public Library of Science. "Major Mid-century Influenza Epidemics Caused By Novel Hybrid Viruses." ScienceDaily. ScienceDaily, 3 March 2008. <www.sciencedaily.com/releases/2008/02/080229075244.htm>.
Public Library of Science. (2008, March 3). Major Mid-century Influenza Epidemics Caused By Novel Hybrid Viruses. ScienceDaily. Retrieved August 27, 2014 from www.sciencedaily.com/releases/2008/02/080229075244.htm
Public Library of Science. "Major Mid-century Influenza Epidemics Caused By Novel Hybrid Viruses." ScienceDaily. www.sciencedaily.com/releases/2008/02/080229075244.htm (accessed August 27, 2014).

Share This




More Health & Medicine News

Wednesday, August 27, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Predicting Heart Transplant Rejection With a Blood Test

Predicting Heart Transplant Rejection With a Blood Test

Ivanhoe (Aug. 27, 2014) Now a new approach to rejection of donor organs could change the way doctors predict transplant rejection…without expensive, invasive procedures. Video provided by Ivanhoe
Powered by NewsLook.com
Better Braces That Vibrate

Better Braces That Vibrate

Ivanhoe (Aug. 27, 2014) The length of time you have to keep your braces on could be cut in half thanks to a new device that speeds up the process. Video provided by Ivanhoe
Powered by NewsLook.com
Smartphone App Tracks Your Heart Rate

Smartphone App Tracks Your Heart Rate

Ivanhoe (Aug. 27, 2014) A new app that can track your heart rate 24/7 is available for download in your app store and its convenience could save your life. Video provided by Ivanhoe
Powered by NewsLook.com
Stroke in Young Adults

Stroke in Young Adults

Ivanhoe (Aug. 27, 2014) A stroke can happen at any time and affect anyone regardless of age. This mother chose to give her son independence and continue to live a normal life after he had a stroke at 18 years old. Video provided by Ivanhoe
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