Monday, April 27, 2015

New Scientist: The Downsides To Using HPAI Poultry Vaccines


Poultry Vaccination - Photo Credit OIE


# 9983


Last week, in The HPAI Poultry Vaccine Dilemma,  I wrote at some length on the problems inherent in turning to a poultry vaccine to control the HPAI H5 viruses spreading across North America.


This is a topic we’ve looked at repeatedly over the years, including in 2012’s Egypt: A Paltry Poultry Vaccine and 2009’s  Indonesia: Debate Over Poultry Vaccination.


Last November we looked at an EID Journal dispatch - Subclinical Highly Pathogenic Avian Influenza Virus Infection among Vaccinated Chickens, China – which addressed many of these concerns, and what they called  the `multiple disadvantages of HPAI mass vaccination, including the creation of vaccine-escape flu variants


Although HPAI vaccines can often prevent serious illness in poultry flocks, they often fail to prevent viruses from spreading, and eventually evolving into new strains.  As these new variants appear, the vaccines become even less effective – turning their use into a gigantic slippery slope. 


One that China, Egypt, Vietnam, and Indonesia have been unable to get off, despite warnings from the OIE that poultry vaccines must be considered a `short-term solution’ and counties must have an `exit strategy’ (see Avian influenza and vaccination: what is the scientific recommendation?).


Although the USDA has steadfastly supported quarantine and culling as the preferred method of dealing with bird flu in the United States, nervous poultry producers are calling for a vaccine option.  


So I’m happy to report that the New Scientist has weighed in on this issue today as well, with an article by Debora MacKenzie.  Follow the link to read:



US farms hit by bird flu – but a vaccine might make things worse

17:08 27 April 2015 by Debora MacKenzie

For similar stories, visit the US national issues and Bird Flu Topic Guides

Bird flu is rampaging across the Midwestern US this week. So far 8 million chickens and turkeys have been destroyed to stop the spread of H5N2, an offspring of Asia's H5N1 bird flu. Minnesota, the top US turkey producer, declared an agricultural emergency after announcing infected farms almost daily for two weeks. Iowa, the top egg producer, killed 3.8 million hens on one farm alone.

US agriculture officials hope the outbreaks will diminish as summer warmth and sunshine destroys flu viruses in the environment. But their bird flu problems may be only beginning. Wild ducks could infect the rest of the continent next autumn.

And while H5N2, unlike H5N1, seems to pose little threat to humans, the $45 billion US poultry industry is already suffering, as China, South Korea and Mexico ban US produce. Producers are calling for a poultry vaccine, and the US Department of Agriculture says it is developing one. But that might just make the problem worse by encouraging the spread of "silent" infections.

(Continue . . .)

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