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July 21st, 2012 
FAKE NEWS for the Zionist agenda
Vaccines are supposed to prevent disease. But two new strains of a nasty poultry disease that have been plaguing chickens in Australia since 2008 have been found to be hybrids of viruses from live vaccines. It is the first time such recombination has been seen between vaccine viruses in the wild.
Live vaccines contain a weakened version of the virus they are designed to treat. There are advantages to their use over vaccines containing dead viruses: because a live virus can replicate, less of it is needed to make a vaccine. “They are essential for vaccinating large numbers of poultry, because you can give them in drinking water or sprays,” says Glenn Browning of the University of Melbourne in Parkville, Australia.
Live vaccines also elicit very broad, lasting immunity, often in the region of the body where the infection normally occurs.
The downside is that live vaccines sometimes mutate back into disease-causing forms, as has happened with polio in humans. The risk of that happening is fairly well known and the process can be monitored. Hybridising between live vaccine strains, or a live vaccine and wild viruses, is less predictable.
In 2007, chicken farmers in Australia were using two commercial, live vaccines for infectious laryngotracheitis (ILT), a lethal poultry disease, that were made from Australian strains of the virus. They then began using a third live vaccine containing a European strain. The following year, they began to see outbreaks of two new ILT strains.
Browning and colleagues have now sequenced the new viruses and found that in each case they arose when the European vaccine strain acquired genes from the Australian vaccine viruses. “We were quite surprised,” he says. The newer strain is half European, half Australian, and has outcompeted the original strain – it now dominates outbreaks in Australia.
Live vaccine viruses are incapable of causing disease – but the hybrids were as deadly as wild ILT, killing 18 per cent of affected flocks.
The nature of ILT may have made it easier for the viruses to hybridise, Browning suspects. Farmers often vaccinate healthy birds during slow-spreading outbreaks, leading to the possibility that chickens might be infected by two different vaccines, which is necessary for them to recombine. Now, he says, regulators will have to find ways to stop that happening.
Not a new trick?
Other vaccines may have been up to similar tricks, he suspects, especially respiratory viruses, where two different viruses might meet on the limited surface area of the nose or throat. “The only way we were able to discover what happened with ILT was because we can now afford to sequence the whole virus. Just five years ago that would have been too expensive,” Browning says. “If we go back and look at preserved samples, we might find that other unexplained disease outbreaks were caused by recombination.”
“This work shows that with live vaccines, we need to pay attention to the evolution of the vaccine strains themselves,” says Andrew Read at the University of Pittsburgh in University Park, an expert in pathogen evolution who was not involved in the research. In fact, he says, “we should pay a lot more attention to the consequences of vaccination for pathogen evolution in general”.
Meanwhile the new viruses might also settle a long-standing question in evolution: what qualities allow one disease-causing microbe to outcompete another? Read suspects the severity of the disease it causes might sometimes help a pathogen prevail. Browning thinks the new ILT is more transmissible than the original disease, and this is why the new strain has almost completely replaced the old ones.
Journal reference: Science, DOI:10.1126/science.1217134
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Vaccination Seasons?
Sat Jul 14 14:47:02 BST 2012 by sevenleafclover
maybe regulating the availability of individual strains of live vaccines to vaccination seasons? This would ensure that no two live vaccination strains are copresent for hybridization.
It makes me wonder though, how often live strain vacinations have hybridized with their wild viral cousins.
More Ammo For Anti-vaccine Boneheads?
Wed Jul 18 17:03:34 BST 2012 by ullrich fischer
I wonder how long it will be before this article spreads.. ie “goes viral” among the conspiracy theorists who are scaring their uninformed victims out of vaccinating their kids the world over. Most of those folks also don’t believe in evolution, so maybe this article should have emphasized that this problem is based on the fact that microbes are continuing to evolve via mechanisms explained in great detail by the notorious Charles Darwin. The word “Evolve” should definitely appear in the headline. This is the kind of article which local papers are likely to pick up… of course they tend to make up their own, more sensational headlines.
More Ammo For Anti-vaccine Boneheads?
Thu Jul 19 07:06:48 BST 2012 by Eric Kvaalen
Most of them do believe in evolution on that scale.
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