Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Low-pathogenic forms of bird flu do cause illness among birds: Mild form of bird flu slows down migration of swans

31.01.2007
Migratory swans carrying a mild form of avian influenza depart from The Netherlands more than a month after their healthy counterparts do. They also feed slower and fly shorter distances.

These insights will be published on January 31, 2007 in PLoS ONE, the International, peer-reviewed, open-access, online publication from the Public Library of Science (PLoS) by scientists from the Netherlands Institute of Ecology (NIOO-KNAW) and the Department of Virology of the Erasmus MC. This contrasts previous ideas that mild forms of bird flu do not cause illness among wild birds. Moreover, these patterns can affect the rate of spread of avian influenza.

Wild birds were thought not to suffer from mild forms of avian influenza. But new data suggest that so-called ‘low-pathogenic’ avian influenza viruses do affect the lives of birds. The Bewick’s swan (Cygnus columbianus bewickii) is a migratory bird that breeds in NW-Russia and overwinters in NW-Europe, especially in The Netherlands. In this species, a team of ecologists and virologists showed that infected individuals initiate their migration by the end of January or early February, while uninfected individuals already do so by the end of December. Also, their next ‘fuelling station’ is only 35 km away instead of the usual 250 km. Sick birds fuel at a lower rate: they take fewer bites per day and their digestion seems to be impaired. Presumably, this is due to their need to channel more energy towards their immune system.

Being ill is no fun for us, but for a migratory bird being ill could potentially mess up its whole calendar for the rest of the year. According to scientist Jan van Gils from NIOO, “Infected swans clearly suffer from their ‘mild’ disease. The late departure from the wintering grounds could lead to late arrival in the breeding grounds, and thus to a lost breeding season. All in all, these low-pathogenic viruses have a much greater impact than previously thought. Because of their slower migration, ill birds get in touch with many more healthy birds passing by them on migration. In this way the virus can spread itself more rapidly than previously thought.”

Acquiring more knowledge about mild but illness-causing avian influenza viruses is very important. Van Gils adds, “These mild virus-types always formed the origin of massive pandemics such as the Spanish Flu. Only such viruses that are non-lethal to birds can be spread easily by (wild or captive) birds, simply because the birds stay alive.” Only after mixing with human flu can such a low-pathogenic avian flu cause the nightmare of a deadly pandemic among humans. “High-pathogenic avian flu that causes death among birds seems to originate from intensive poultry farms.”

In the Dutch study 25 swans were investigated. The birds were caught in polder Wieringermeer (NW-Netherlands) last winter and were measured, weighed and screened for the prevalence of avian influenza viruses. Twelve birds were equipped with a GPS attached to their neck collar (80 g in total). This enabled the researchers to follow the birds’ movements in great detail. When within 300 m of the bird, all “travel data” were downloadable by wireless modern technology. Birds were found back by volunteer bird watchers reading and reporting the code on each bird’s neck collar. Among the twelve neck-collared birds, two were infected with bird flu: type H6N2 and H6N8. These mild virus types are common among free-living waterfowl. From antibodies found back in blood samples it could be concluded that a few more individuals had been infected before but were fully recovered and behaved as the other healthy birds. Both birds that were infected last winter have returned this winter and seem fully recovered too.

Froukje Rienks | alfa
Further information:
http://www.plosone.org
http://www.nioo.knaw.nl

More articles from Ecology, The Environment and Conservation:

nachricht Dispersal of Fish Eggs by Water Birds – Just a Myth?
19.02.2018 | Universität Basel

nachricht Removing fossil fuel subsidies will not reduce CO2 emissions as much as hoped
08.02.2018 | International Institute for Applied Systems Analysis (IIASA)

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Explanation for puzzling quantum oscillations has been found

So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics

Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...

Im Focus: Dozens of binaries from Milky Way's globular clusters could be detectable by LISA

Next-generation gravitational wave detector in space will complement LIGO on Earth

The historic first detection of gravitational waves from colliding black holes far outside our galaxy opened a new window to understanding the universe. A...

Im Focus: Entangled atoms shine in unison

A team led by Austrian experimental physicist Rainer Blatt has succeeded in characterizing the quantum entanglement of two spatially separated atoms by observing their light emission. This fundamental demonstration could lead to the development of highly sensitive optical gradiometers for the precise measurement of the gravitational field or the earth's magnetic field.

The age of quantum technology has long been heralded. Decades of research into the quantum world have led to the development of methods that make it possible...

Im Focus: Computer-Designed Customized Regenerative Heart Valves

Cardiovascular tissue engineering aims to treat heart disease with prostheses that grow and regenerate. Now, researchers from the University of Zurich, the Technical University Eindhoven and the Charité Berlin have successfully implanted regenerative heart valves, designed with the aid of computer simulations, into sheep for the first time.

Producing living tissue or organs based on human cells is one of the main research fields in regenerative medicine. Tissue engineering, which involves growing...

Im Focus: Light-induced superconductivity under high pressure

A team of scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg investigated optically-induced superconductivity in the alkali-doped fulleride K3C60under high external pressures. This study allowed, on one hand, to uniquely assess the nature of the transient state as a superconducting phase. In addition, it unveiled the possibility to induce superconductivity in K3C60 at temperatures far above the -170 degrees Celsius hypothesized previously, and rather all the way to room temperature. The paper by Cantaluppi et al has been published in Nature Physics.

Unlike ordinary metals, superconductors have the unique capability of transporting electrical currents without any loss. Nowadays, their technological...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Save the date: Forum European Neuroscience – 07-11 July 2018 in Berlin, Germany

02.05.2018 | Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

 
Latest News

Supersonic waves may help electronics beat the heat

18.05.2018 | Power and Electrical Engineering

Keeping a Close Eye on Ice Loss

18.05.2018 | Information Technology

CrowdWater: An App for Flood Research

18.05.2018 | Information Technology

VideoLinks
Science & Research
Overview of more VideoLinks >>>