|Spread of HPAI H7N9 Since January 2017|
Last week, in CHINA: HPAI H7N9 Expands Its Range, we looked at the northward expansion of HPAI H7N9 from where it first emerged last January in China's southern Guangdong province - to Hunan, Fujian, Guangxi, and Hebei Provinces.
Yesterday, the FAO confirmed in their weekly update the HPAI strain has also been detected on a chicken farm in Henan Province, about 800 miles north of its first detection four months ago.This from China's MOA.
Henan Province, Pingdingshan City, Lushan County, a poultry H7N9 influenza epidemic situation has been effectively controlled
Date: 2017-05-12 16:42 Source:
May 3, Henan Province, Pingdingshan City Lushan County Veterinary Department in the monitoring found in some farms breeding chickens suspected bird flu symptoms, the incidence of 7500, died 5770 only. May 7, Henan Province, animal disease prevention and control center for the diagnosis of suspected avian flu outbreak.
May 12, confirmed by the National Avian Influenza Reference Laboratory, the outbreak for the H7N9 flu epidemic. After the epidemic, the local in accordance with the relevant plans and control technical requirements, adhere to the law prevention and control, scientific prevention and control, and effectively do the epidemic disposal work, has been culling and harmless treatment of poultry 77040 only. At present, the epidemic has been effectively controlled.
Aside from the concern that this HPAI H7N9 virus produces significant morbidity and mortality in poultry, last week in Eurosurveillance: Biological Characterisation Of (HPAI) A(H7N9) Viruses In Humans, we saw evidence that this HPAI version retains the ability to infect both birds and humans, and in fact, may be slightly more infectious in both than the LPAI version. The authors wrote:
Our data show that the HPAI H7N9 viruses retained dual receptor binding properties, with slightly increased binding preference for both receptors compared with LPAI H7N9 (AnH1) viruses. . . . . The persisting preference for both avian- and human-type receptors of HPAI H7N9 viruses may result in their circulation in poultry and possible transmission among humans.While there is still much that we don't know about this HPAI variant, its appears to be biologically `fit' enough to spread reasonably rapidly and is able to compete with the far better established LPAI strains.
Although we've only been notified of 3 human infections with the HPAI version of the virus, it isn't at all clear whether the weekly updates by the NHFPC currently differentiates between LPAI and HPAI human infections.How this emerging HPAI strain will ultimately impact the spread and evolution of H7N9 remains unknown, but it's emergence is yet another sign of the growing diversity of this complex, and record breaking, avian flu subtype.