Friday, August 18, 2017

China MOA Confirms H5N6 Outbreak In Quail - Guizhou Province

Credit Wikipedia

















#12,698


Less than three weeks after announcing a large outbreak of HPAI H5N1 in Inner Mongolia, China's Ministry of Agriculture has announced an outbreak of HPAI H5N6 in quail farms in Guizhou Province.

Due to the imprecise nature of translation software, it isn't entirely clear whether more than one farm was affected, but the report refers to `some farmers'

Luodian County, Guizhou province occurred poultry with H5N6 subtype highly pathogenic bird flu
Issued by: Ministry of Agriculture press office Date: 2017-08-18 14:27 Keywords: bird flu; epidemic; Guizhou

  Ministry of Agriculture press office issued August 18, Luodian County, Guizhou province occurred poultry with H5N6 subtype highly pathogenic bird flu.

  August 10, Luodian County, Guizhou province some farmers rearing of quail suspected bird flu symptoms appear, the incidence 13103, died 9752. August 13, animal disease prevention and control center in Guizhou Province diagnosed with suspected bird flu. August 18, by the National Avian Influenza Reference Laboratory confirmed the outbreaks as H5N6 subtype highly pathogenic bird flu.

  After the outbreak, according to the relevant local prevention plans and technical specifications, adhere to the prevention and control law, science and prevention and control, really good job epidemic disposal, have been culling and safe disposal of poultry 8110. Currently, the outbreaks has been effectively controlled.

While H5N6 has been known to infect humans (n=16), it has been 9 months since the last reported case.  In the meantime, we've seen H5N6 move beyond China, Vietnam, and Laos and into South Korea, Japan, and Taiwan. 
As it has spread, it has reassorted numerous times, producing multiple genotypes (see Emerg. Microbes & Inf.: Human Infections With A Novel Reassortant H5N6).
Due to the extensive use of H5 vaccines in Chinese poultry, large outbreaks of HPAI H5 viruses in commercial flocks have become relatively rare, although there is ample evidence that these viruses continue to circulate widely as sub-clinical infections. 
Subclinical Highly Pathogenic Avian Influenza Virus Infection among Vaccinated Chickens, China). 
Study: Recombinant H5N2 Avian Influenza Virus Strains In Vaccinated Chickens 
EID Journal: Subclinical HPAI In Vaccinated Poultry – China

Seeing two `breakout' events so close together - particularly this late in the summer - is a bit unusual.
This fall China will roll out a new combination H5 + H7 poultry vaccine (see China MOA Orders HPAI H7N9 Vaccine Deployed Nationwide This Fall) which they hope will help control HPAI H5 viruses like H5N1, H5N6 and H5N8, plus the rapidly spreading LPAI and HPAI versions of H7N9.
After more than a dozen years of use in China, however, poultry vaccines have not proved to be a panacea for bird flu. For more on some of the challenges of controlling avian flu with poultry vaccines, you may wish to revisit:
Virology: Selection Of Antigenic Variants Of An H5N1 HPAI Virus In Vaccinated Chickens
New Scientist: The Downsides To Using HPAI Poultry Vaccines

PLoS Bio: Imperfect Poultry Vaccines, Unintended Results