Several outbreaks of severe bird flu in Europe and Asia have been reported in recent days to the World Organisation for Animal Health (OIE), in a sign the virus is spreading quickly again.
The highly pathogenic avian influenza, commonly called bird flu, has put the poultry industry on alert, seeing as previous outbreaks have led to the culling of tens of millions of birds. Outbreaks could also lead to trade restrictions.
The bird flu outbreaks have also attracted the attention of epidemiologists because the bird flu can be transmitted to humans. China has reported 21 human infections with the H5N6 subtype of avian influenza so far this year, more than in the whole of 2020, reports CNN.
On Monday, an outbreak on a poultry farm in Chungcheongbuk-do, South Korea resulted in 700,000 chickens being slaughtered, according to the OIE.
Japan also reported its first outbreak of the 2021 winter season, at a poultry farm in the northeast of the country, the OIE said, confirming a statement last week by Japan’s agriculture ministry. The serotype in this outbreak was H5N8.
In Europe, most recently, Norway reported an H5N1 bird flu outbreak in the Rogaland region in a flock of 7,000 birds, the OIE said.
The Belgium government has put the country on an increased risk for the bird flu, ordering all poultry to be kept indoors, as of Monday after a pathogenic variant of bird flu was identified in a wild goose near Antwerp, reports The Guardian. Similar moves have been made by the governments of France and the Netherlands in the past several weeks.
Earlier this month, a bird flu prevention zone was declared across Great Britain, legally requiring all bird keepers to follow strict biosecurity measures after a flock of poultry was culled near Dundee in Scotland in response to a bird flu outbreak.
Avian Flu is similar to other influenzas
Bird flu is similar to swine flu, dog flu, horse flu, and human flu as an illness caused by strains of influenza viruses that have adapted to a specific host. Of the three types of influenza viruses, (A, B, and C), influenza A virus is a zoonotic infection with a natural reservoir almost entirely in birds, according to the CDC.
The concern with Avian flu is that it can also stably adapt and sustain person-to-person transmission. Pigs can also be infected with human, avian, and swine influenza viruses, allowing for mixtures of genes to be created.
This means that a new virus is created, which can cause an antigenic shift to a new influenza A virus subtype which most people have little to no immune protection against.
Most human cases of the avian flu are a result of either handling dead infected birds or from contact with infected fluids. It can also be spread through contaminated surfaces and droppings.
Although it is easy for humans to contract the infection from birds, human-to-human transmission is more difficult without prolonged contact. However, public health officials are concerned that strains of avian flu may mutate to become easily transmissible between humans.
