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Avian Flu in the News
Promising preclinical results with live attenuated H5N1 vaccines
Several approaches are in progress to develop vaccines against the avian flu variety of the influenza virus. Kanta Subbarao (National Institutes of Health) and colleagues are working
on live attenuated vaccines, which have the potential to elicit a strong, broad, and lasting immune response. As they now report in the international open-access medical journal PLoS Medicine, results from mice and
ferrets (the rodent flu model of choice) are very encouraging and pave the way to testing these vaccines in human volunteers.
The researchers developed vaccines using 3 artificially constructed, weakened forms of the influenza virus. The 3 vaccine viruses were constructed using flu virus proteins other than
H and N from artificially weakened (attenuated) strains of influenza. These were combined with H and N proteins from H5N1 viruses isolated from human cases during three different years: 2004, 2003, and 1997. They
grew larger quantities of the resulting viruses in hen eggs, and tested the vaccines in chickens, ferrets, and mice.
In tests of safety, the study found that, unlike the natural viruses from which they were derived, the vaccine strains did not cause death when
injected into the bloodstream of chickens, and did not even cause persistent infection when given through the birds' breathing passages. Similarly, while the natural viruses were lethal in mice at various doses,
the vaccine strains did not cause death even at the highest dose. In ferrets, infection with the vaccine strains was limited to the upper respiratory tract, while the natural viruses spread eadily to the lungs.
In tests of protection, all mice that had received any of the 3 vaccines survived following injection with any of the natural viruses (so-called viral challenge), while unvaccinated
mice died following viral challenge. This occurred even though standard blood tests could not detect a strong immune responses following a single dose of vaccine. Challenge virus was detected in the lungs of the
immunized mice, but at lower levels than in the unvaccinated mice. Mice given two doses of a vaccine showed stronger immunity on blood tests, as well as almost complete protection from respiratory infection
following challenge. In addition, mice and ferrets that had received two doses of vaccine were protected against challenge with H5N1 strains from more recent outbreaks in Asia that differed substantially from the
strains that were used for the vaccine.
This study shows that live attenuated vaccine based on a single H5N1 virus strain can provide protection (in mice and ferrets, at least) against different H5N1 viruses that emerge
years later. One of the vaccines is now being tested in human volunteers who participate in carefully conducted clinical trials.
Bird flu (avian influenza) - MayoClinic.com
Housecall, our weekly general-interest e-newsletter, keeps you up to date on a wide variety of health topics with timely, reliable, practical information, recipes, blogs, questions and answers with Mayo Clinic ...
Canine flu hits 33 states; does your dog need a vaccine? - WVLT
KNOXVILLE, Tenn. (WVLT)--There's the avian flu, then the swine flu and there's even the canine influenza. It actually took the life of one dog in Virginia. There's a new vaccine, and a local vet tells us it helps ...
H5N1 Avian Flu virus has mutated, study says - Mister-info.com
Researchers involved in a study at the University of Wisconsin have discovered that the H5N1 Avian Flu virus has mutated into a strain that may make humans more vulnerable to the disease. Prior to the study, it was ...
Media Censoring Lethal Side Effects Of Flu Remedies - American Free Press
... prepare for the possible bird flu pandemic, of which $1 billion was solely dedicated to the purchase and distribution of Tamiflu. Bush said a minimum of 200,000 Americans were going to die from the avian flu ...
Protecting Your Backyard Chicken Flock from Avian Bird Flu - Associated Content
Avian flu (also called "Bird Flu" or "H5N1") is a strain of influenza that is passed through birds. It has been found in wild bird populations and in poultry, but has not yet spread to poultry populations ...
Tracking Bird Flu, One Poop at a Time - Wired News
may help scientists track the spread of bird flu — with olfactory assistance from properly trained animals. Scientists have trained mice to identify the poop of ducks infected with avian influenza, chemical ...
Backyard Chicken Keepers Help Fight Avian Disease - Tree Hugger
According to a press release from the USDA's Animal and Plant Health Inspection Service (APHIS), chicken keepers are forming communities of like-minded soulds—both online and in the real world—through sites like ...
Indonesia reports 100th human death from bird flu - Mister-info.com
Two people, a nine year old boy and a 23-year-old woman from Jakarta in Indonesia, have died from the H5N1 Avian Flu virus marking the country's 100th death from the disease. Both died on Sunday, January 27. "The ...
Avian flu still likely to strike in humans, says Welsh expert - WalesOnline
THE threat of bird flu crossing over to humans and igniting a pandemic remains real, one of Wales’ leading experts on health and disaster management has claimed. Alan Hawley, who until recently was the UK’s ...
8 Ways Swine Flu Is Changing Society - MSN Health & Fitness
The H1N1 virus actually has avian, swine and human genes, and may not even make pigs sick, scientists say. Unfortunately for pork producers, “swine flu” has become the common name for this flu. 5. Tourism to ...
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