Bird flu outbreaks causing alarm across Asia, Europe

November 30, 2016

Public health officials across Asian countries are alarmed at the rising number of recent bird flu outbreaks in the region, reminiscent of the fatal H5N1 strain that has taken the lives of more than 450 people since the mid-2000s.

For the first time in nearly two years, Japan is culling around 310,000 chickens at a farm in the village of Sekikawa in the Niigata prefecture after 40 birds were found dead from H5 bird flu. The culling will continue until December 2, according to a prefectural official.

Meanwhile, about 16,500 ducks were being culled in the Aomori prefecture after some tested positive for bird flu, according to a statement on the prefecture’s website.

Authorities in Tokyo did not immediately identify the subtype of the H5 virus.

This follows the culls of more than 1.5 million birds in South Korea. The outbreaks highlight the ongoing danger that new varieties of avian influenza may emerge from crowded poultry farms, especially in less developed parts of Asia, and then spread to humans.

“As well as further examining the circumstances of the outbreak, we have strengthened disinfection of areas surrounding the affected farms, and set up sterilization points on the main roads,” said Yoshihide Suga, Japan’s chief cabinet secretary.

South Korea is also on high alert, announcinga temporary nationwide standstill order for poultry farms and related transport over the weekend in a bid to contain a spread of the H5N6 bird flu strain, a new subtype that emerged from China in 2014. It is a severe strain that can spread to humans and has killed at least nine people.

Earlier this week, Seoul’s agriculture ministry has confirmed 41 cases of the highly pathogenic infection in the central Gyeonggi province and South Jeolla province in the south, up from six last week, despite the standstill order. Nearly 1.7million chickens and ducks have so far been culled, with authorities pointing to migratory birds as the source of the virus.

“The spreading pace of the animal disease is so fast that it will likely hit the western region and the entire nation,” the ministry said, adding that it had ordered provincial governments to open emergency operations centers and strengthen hygiene checks.

Influenza viruses are divided into subtypes based on two proteins found on their surface. There are 18 different subtypes of hemagglutinin (H) and 11 different subtypes of neuraminidase (N). H1N1 and H3N2 are the main subtypes currently affecting humans. Even within these subtypes, different strains circulate from year to year.

Europe has also been wrestling with the H5 avian flu, as another severe strain, H5N8, hit several countries in the region. This led to the culling of thousands of poultry after being detected in wild ducks in Northern France.

Germany, Switzerland, and Romania have also seen outbreaks. The Netherlands has slaughtered about 190,000 ducks at six farms following an outbreak. In India, Delhi zoo was forced to close this year after a spate of bird deaths linked to bird flu.

The H5N8 virus has never been detected in humans but it led to the culling of millions of farm birds in Asia, mainly South Korea, in 2014 before spreading to Europe.

Although the World Organization for Animal Health has warned of more outbreaks of the H5N8 as wild birds, which are believed to transmit the virus, migrate southward.

However, the World Health Organization has played down the threat to human safety, suggesting that new cases will continue but the disease is unlikely to evolve to spread directly from human to human. Transmission between humans would allow a flu strain to spread more rapidly through the population, turning the disease into a dangerous pandemic.

“Most human cases were exposed to H5 viruses through contact with infected poultry or contaminated environments, including live poultry markets,” the WHO said in a recent report. “Evidence suggests that… H5 viruses have not acquired the ability of sustained transmission among humans.”

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