Bird flu: In the plumage the secret of virus spread success

Jun 25, 2010

International team of Italy-US scientists reports discovery of a new mechanism of avian influenza virus circulation and transmission in nature.

A team of scientists, led by Mauro Delogu, virologist from the Veterinary Faculty of the Bologna University and researchers from the Istituto Superiore di Sanità, Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia and St. Jude Children's Research Hospital (Memphis, Tennessee) have discovered a new way of transmission. The study, which offers new insights into ecology, surveillance and prevention strategies of avian influenza viruses (AIVs), may ultimately be important in the fight against influenza. The study has been published in a recent issue (June, 25/2010) of .

The scientists actually discovered that the preen oil gland secretions, by which all aquatic birds make their feathers waterproof, support a natural mechanism that concentrates AIVs from water onto birds' bodies. They found that a progressive virus "sticking" on feathers occurs because AIV-contaminated waters interact with the preen oil gland secretion. Since waterbirds use to spread preen oil over their own (self-preening) or other birds' (allo-preening) plumage, it is easily understandable how these preening activities could facilitate the diffusion of the viruses in nature.

The discovery, adds Delogu, has also important implications in the surveillance of avian influenza viruses.

In fact, virus on feathers could escape detection by the current surveillance strategies which assay the virus secreted in the cloacal and tracheal samples only. Lack of detection of these viruses may greatly complicate surveillance and rapid responses to new emergence and spread. For this reason, Delogu said, in routine surveillance programs, additional sampling methods could be necessary to detect AIVs on birds' bodies. Our results also suggest that a preened body surface could be the common denominator that explains how AIV infection occurs in different taxonomic groups of aquatic birds and future studies are needed to determine the common uropygial component that could promote interaction with AIVs in all aquatic bird species. Studies to reproduce the preening-mediated AIV infection mechanism in the animal model are in progress.

Finally, Delogu concludes, our discovery really opens a door to explain the highly pathogenic H5N1 circulation and persistence in Eurasia, as well as the only recorded human case of fatal infection passed from wild birds in February 2006. All infected humans were involved in defeathering of dead wild swans after a massive die-off of these aquatic birds occurred in Azerbaijan.

Explore further: Global Ebola toll rises to 5,689: WHO

add to favorites email to friend print save as pdf

Related Stories

New host species for avian influenza identified

May 11, 2007

An eight-year surveillance study, which included more than 36,000 wild migratory birds tested for low pathogenic avian influenza, details new data on host species, prevalence, and temporal and geographical variation of avian ...

Bird flu virus strain found in Maryland

Sep 12, 2006

U.S. scientists say an H5N1 avian influenza virus found earlier this month in Maryland is a low pathogenic subtype and poses no threat to humans.

North American birds in avian flu study

Oct 23, 2006

U.S. scientists say they've found the common wood duck and laughing gull are susceptible to the H5N1 avian influenza virus and could transmit the disease.

Recommended for you

Global Ebola toll rises to 5,689: WHO

2 hours ago

The World Health Organization said Thursday that the global death toll from the Ebola virus had increased to 5,689 out of a total of 15,935 cases of infection, mainly in western Africa.

Ebola vaccine promising in first human trials

12 hours ago

Researchers say they're a step closer to developing an Ebola vaccine, with a Phase 1 trial showing promising results, but it will be months at the earliest before it can be used in the field.

At one month, US Ebola monitors finding no cases

15 hours ago

The U.S. program that requires weeks of monitoring for travelers from African countries with Ebola reaches the one-month mark Thursday. And so far, no cases of the disease have turned up.

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.