Featured Research

from universities, journals, and other organizations

Satellite data reveals why migrating birds have a small window to spread bird flu

Date:
September 6, 2010
Source:
Wiley - Blackwell
Summary:
In 2005 an outbreak of the H5N1 'bird flu' virus in South East Asia led to widespread fear with predictions that the intercontinental migration of wild birds could lead to global pandemic. Such fears were never realised, and now new research reveals why the global spread of bird flu by direct migration of wildfowl is unlikely, while also providing a new framework for quantifying the risk of avian-borne diseases.

In 2005 an outbreak of the H5N1 'bird flu' virus in South East Asia led to widespread fear with predictions that the intercontinental migration of wild birds could lead to global pandemic. Such fears were never realised, and now research published in the British Ecological Society's Journal of Applied Ecology reveals why the global spread of bird flu by direct migration of wildfowl is unlikely, while also providing a new framework for quantifying the risk of avian-borne diseases.

The highly pathogenic H5N1 bird flu virus is primarily a disease of poultry, often resulting in mass mortality for infected flocks. However, the virus can also infect other species, including wild birds and humans. Experimental infection has also revealed that some wild ducks, geese and swans can carry the virus asymptomatically, that is before the symptoms of the virus become apparent, meaning that they have the potential to spread the virus as they migrate.

"The potential risks to humans led to extensive media coverage often focusing on migratory birds, which fuelled public concern and led to calls for the mass culling of wild birds," said lead author Dr Nicolas Gaidet. "However, the actual risk of H5N1 spread through migratory birds depended on whether infected individuals were capable of migratory movements while shedding virus, and the distance over which such individuals could travel. Our research has answered these questions using analysis of infection and migratory routes and timings for many bird species."

Dr Gaidet's team analysed 228 birds from 19 species using satellite telemetry from 2006 to 2009 over the bird flu affected areas of Asia, Europe and Africa. The results indicated that migrating wildfowl do have the potential to disperse H5N1 over extensive distances as mass migration can result in infected birds covering as much as 2900km before symptoms become apparent.

However, while this is theoretically possible the team found that direct virus dispersal by migrating birds would require asymptomatic infection to coincide precisely with the migration season. The results revealed a very small 'window' of between 5 to 15 days when dispersal of the virus over 500 km could occur.

It is crucial to the spread of disease over such a distance that an infected bird must not be showing the symptoms of infection. If the symptoms are evident then it is highly likely that the individual may not migrate, or at least they will be unable to cover the distance as well as a healthy bird.

Along with the precise timing required to spread the virus across the maximum distance, the migrating birds would also have to fly the shortest route possible, as quickly as possible. However, the team found that most migrating wildfowl stop at various staging posts throughout the trip for periods longer than the asymptomatic duration period. Virus transfer between staging birds or infection from the environment would allow a greater potential for spread, and while neither of these routes of transmission are well documented, the latter is most likely.

"Our results indicate that individual migratory wildfowl do have the potential to disperse H5N1 over extensive distances, however the likelihood of such intercontinental virus dispersal by individual wildfowl is very low," concluded Gaidet. "Our results provide a detailed quantitative framework for the dispersive potential of avian borne viruses, which will help to better understand the risk posed by other avian-borne diseases such as the West Nile Virus."


Story Source:

The above story is based on materials provided by Wiley - Blackwell. Note: Materials may be edited for content and length.


Journal Reference:

  1. Nicolas Gaidet, Julien Cappelle, John Y. Takekawa, Diann J. Prosser, Samuel A. Iverson, David C. Douglas, William M. Perry, Taej Mundkur, Scott H. Newman. Potential spread of highly pathogenic avian influenza H5N1 by wildfowl: dispersal ranges and rates determined from large-scale satellite telemetry. Journal of Applied Ecology, 2010; DOI: 10.1111/j.1365-2664.2010.01845.x

Cite This Page:

Wiley - Blackwell. "Satellite data reveals why migrating birds have a small window to spread bird flu." ScienceDaily. ScienceDaily, 6 September 2010. <www.sciencedaily.com/releases/2010/09/100903072653.htm>.
Wiley - Blackwell. (2010, September 6). Satellite data reveals why migrating birds have a small window to spread bird flu. ScienceDaily. Retrieved August 22, 2014 from www.sciencedaily.com/releases/2010/09/100903072653.htm
Wiley - Blackwell. "Satellite data reveals why migrating birds have a small window to spread bird flu." ScienceDaily. www.sciencedaily.com/releases/2010/09/100903072653.htm (accessed August 22, 2014).

Share This




More Plants & Animals News

Friday, August 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Farm Resurgence Grows With Younger Crowd

Farm Resurgence Grows With Younger Crowd

AP (Aug. 22, 2014) — New England farms are seeing a surge in younger farm hands as the 'buy local' food movement grows across the country. (Aug. 22) Video provided by AP
Powered by NewsLook.com
Drug Used To Treat 'Ebola's Cousin' Shows Promise

Drug Used To Treat 'Ebola's Cousin' Shows Promise

Newsy (Aug. 21, 2014) — An experimental drug used to treat Marburg virus in rhesus monkeys could give new insight into a similar treatment for Ebola. Video provided by Newsy
Powered by NewsLook.com
Terrifying City-Dwelling Spiders Are Bigger And More Fertile

Terrifying City-Dwelling Spiders Are Bigger And More Fertile

Newsy (Aug. 21, 2014) — According to a new study, spiders that live in cities are bigger, fatter and multiply faster. Video provided by Newsy
Powered by NewsLook.com
Did Russia Really Find Plankton On The ISS? NASA Not So Sure

Did Russia Really Find Plankton On The ISS? NASA Not So Sure

Newsy (Aug. 21, 2014) — Russian cosmonauts say they've found evidence of sea plankton on the International Space Station's windows. NASA is a little more skeptical. 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