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cHeroKee
05-21-2012, 04:24 PM
Pandemic 2009 H1N1 vaccination produces antibodies against multiple flu strains

Discovery brings researchers closer to goal of 'universal' flu vaccine

The pandemic 2009 H1N1 vaccine can generate antibodies in vaccinated individuals not only against the H1N1 virus, but also against other influenza virus strains including H5N1 and H3N2. This discovery adds an important new dimension to the finding last year that people infected with pandemic 2009 H1N1 virus produced high levels of antibodies that were broadly cross-reactive against a variety of flu strains.

Development of a "universal" influenza vaccine that protects against multiple viral subtypes has long been the goal of immunologists working to overcome the requirement for a new vaccine during each flu season and the need for a rapid response to potentially dangerous mutations.

The new discovery brings the researchers closer to being able to design a pan-influenza vaccine that reliably induces broadly cross-reactive antibodies at sufficiently high levels to protect against different influenza subtypes.

The findings are published this week in the Proceedings of the National Academy of Sciences (PNAS). The researchers are from Emory University, the University of Chicago, and the National Institute of Allergy and Infectious Diseases (NIAID) of the National Institutes of Health (NIH).

The researchers analyzed B cell (antibody) responses in 24 healthy adults immunized with the inactivated pandemic 2009 H1N1 vaccine. Vaccination caused a rapid increase in production of monoclonal antibodies that were capable of neutralizing multiple flu strains. Three of the antibody types also were able to stick to the "stalk" region of the virus that does not change as much as other regions and thus could provide a basis for a vaccine with broader and more reliable protection.

Antibodies that are broadly reactive against multiple influenza strains are rarely seen in people after infection or vaccination with seasonal flu, the authors note. In the 24 vaccinated individuals in the current study, the majority of flu antibodies neutralized more than one influenza strain and also seemed to be the result of B-cell memory resulting from previous exposure to other flu strains.

"Since discovering last year that people infected with the H1N1 2009 virus produced antibodies against multiple flu strains, our goal has been to test this ability in vaccinated individuals," says senior author Rafi Ahmed, PhD, director of the Emory Vaccine Center and a Georgia Research Alliance Eminent Scholar.

"Our new finding is a key step in the development of a vaccine that can produce high levels of antibodies that protect against multiple flu strains, including challenging mutations that have the potential for widespread illness and death."

The next step for the research team will be to improve on their results and develop a vaccine that produces high levels of antibodies and can reliably protect against multiple flu subtypes.

LEVE
05-21-2012, 04:35 PM
Two words: "Swine Flu"

I don't believe 'em, they've not got a good track record.

cHeroKee
06-22-2012, 01:26 PM
Pandemic bird flu transmissible by air in ferrets

<small> June 22, 2012 (http://medicalxpress.com/archive/22-06-2012/) in Diseases, Conditions, Syndromes (http://medicalxpress.com/diseases-news/)</small>


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Five mutations in a pandemic avian influenza virus can allow airborne transmission of the virus between ferrets, according to a study in the June 22 issue of Science.
(HealthDay) -- Five mutations in a pandemic avian influenza virus can allow airborne transmission of the virus between ferrets, according to a study in the June 22 issue of Science.

Sander Herfst, Ph.D., from the Erasmus Medical Center in Rotterdam, Netherlands, and colleagues used site-directed mutagenesis to genetically modify the human pathogenic avian influenza (http://medicalxpress.com/tags/pathogenic+avian+influenza/) A/H5N1 virus, and subsequently serial passaged the virus in ferrets. The authors sought to determine whether A/H5N1 virus could acquire mutations that would increase the risk of mammalian transmission.

The researchers found that the modified virus evolved additional novel mutations in ferrets. The new viruses became airborne transmissible, although none of the recipients died after airborne infection with the modified virus. The airborne-transmitted viruses had five consistent mutations, of which four were in the host receptor-binding protein hemagglutinin and one was in the polymerase complex protein basic polymerase 2. The viruses were susceptible to treatment with oseltamivir and reacted with antisera raised against H5 influenza.

"Thus, avian A/H5N1 influenza viruses can acquire the capacity for airborne transmission between mammals without recombination in an intermediate host and therefore constitute a risk for human pandemic influenza (http://medicalxpress.com/tags/pandemic+influenza/)," Herfst and colleagues conclude.

kenh
06-22-2012, 03:00 PM
“The viruses were susceptible to treatment with oseltamivir and reacted with antisera raised against H5 influenza.”
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"Thus, avian A/H5N1 influenza viruses can acquire the capacity for airborne transmission between mammals without recombination in an intermediate host and therefore constitute a risk for human pandemic influenza,"

I notice that they didn't say what would happen if the mammal were not treated at all. If humans were to get this new mutation from airborne exposure and did not get the correct treatment within a certain amount of time would it then become deadly to that human? I am not in favor of letting a ferret or any other animal suffer with a virus to see if they would die without treatment, but it is a question that ultimately needs answering for the sake of human lives.:smile (3):