Monday, November 21, 2016

China: Fatal H5N6 Infection In Hunan Province


It's been over 5 months since the last reported H5N6 human infection in China (see HERE), as bird flu of all type tends to subside over the warmer summer months.

With the return of fall weather, however, conditions have become favorable for avian flu spread in the Northern Hemisphere, as evidenced by flurry of reports out of Europe and South Korea.

Ten days ago we saw two H7N9 cases reported in Zhejiang and Jiangsu Provinces, and today we have a report from Xinhua News of Hunan Province's 3rd case since April 2016.   I've not yet found an official statement on the Hunan CDC website but the FAO has published a notification.   

Woman dies from H5N6 avian flu in central China

Source: Xinhua | November 21, 2016, Monday

A woman died after contracting H5N6 avian flu in central China's Hunan province, local health authorities said Monday.
The woman, 47-year-old Luo, was a farmer from Shaoyang City. She was admitted to a local hospital last Friday when her health condition had already become critical, and died on Sunday, according to the Hunan provincial disease control center (CDC).
Luo had contact with dead poultry before she fell ill. No human-to-human transmission has been reported yet.
Experts from the CDC warned people who have had contact with live poultry to stay alert and for others to stay away from poultry and excrement. 

Up until December of last year, during H5N6's first 18 months of spread, we'd only seen 4 human infections reported by Chinese officials.

Since then, we've seen 11. 

Exactly what has contributed to this uptick in human cases is unknown, although we do have evidence that the virus has evolved (and reassorted) since it first emerged in the spring of 2014.

Over the past eight months we've looked at the continuing evolution of these H5N6 viruses (see Novel Reassortant H5N6 Viruses In Humans, Guangdong China and J. Virology: H5N6 Receptor Cell Binding & Transmission In Ferrets).

The EID study found that while H5N6's  HA (H5 clade and NA (N6) genes have remained fairly stable, its internal genes have changed - as a result of continued reassortment - since it emerged in 2014.

And last May the WHO released an assessment which noted not only the increase in human infections, but the ongoing evolution of the virus as well.

Avian influenza A(H5) viruses
According to the animal health authorities in China 3,4 , influenza A(H5N6) viruses have been detected in poultry in recent months in many provinces in the country, including those reporting human cases. Recent publications indicate ongoing evolution of avian influenza A(H5N6) viruses through reassortment with other avian influenza viruses resulting in viruses with different internal genes. 5,6

To date, no changes in transmissibility in humans have been detected as a result of these reassortant 1viruses. Surveillance is continuing in both human and animal populations to monitor for further virus evolution. All recent avian influenza A(H5N6) viruses that have been tested remain susceptible to the neuraminidase inhibitor class of antiviral drugs.

With H5N6 now apparently on the move via migratory birds, it adds yet another layer of complexity to our global avian flu threat.   For more on the history and evolution of this emerging viral threat, you may wish to revisit:

CJP Peds: Severe H5N6 Infection In An 11 Year Old Child
H5N6: The Other HPAI H5 Threat
H5N6 Rising: Infecting Birds, Humans, & Even Cats
EID Journal: Influenza A(H5N6) Virus Reassortant, Southern China, 2014

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