Governments should consider vaccinating poultry against avian influenza, which has killed hundreds of millions of birds and infected mammals worldwide, to prevent the virus from turning into a new pandemic, Reuters reported, citing the head of the World Organisation for Animal Health (WOAH).

The severity of the current outbreak of avian influenza, commonly called bird flu, and the economic and personal damage it has caused, has led governments to reconsider vaccinating poultry. However, some, like the United States, remain reluctant mainly because of the trade curbs this would entail.

"We are coming out of a COVID crisis where every country realised the hypothesis of a pandemic was real," WOAH director general Monique Eloit told Reuters in an interview.

"Since almost every country that does international trade has now been infected, maybe it's time to discuss vaccination, in addition to systematic culling which remains the main tool (to control the disease)," she said.

The Paris-based WOAH is holding a five-day general session from Sunday, and will focus on global control of highly pathogenic avian influenza, or HPAI.

A WOAH survey showed only 25% of its member states would accept imports of products from poultry vaccinated against HPAI.

The European Union's 27 member states agreed last year to implement a bird flu vaccine strategy.

France, which spent about one billion euros ($1.10 billion) in 2021/22 to compensate the poultry industry for massive cullings, is set to be the first EU country to begin a vaccination programme, starting with ducks.

"It is our responsibility to use other tools that are now available such as vaccination. And this, for animal health, for public health but also to respond to societal challenges," French Agriculture Minister Marc Fesneau said at the launch of the WOAH General Session.

Eloit said the EU move towards vaccination could prompt others to follow.

"If a bloc like the EU, which is a large exporter, starts moving in that direction, it will have a ricochet impact," Eloit said.

The US Department of Agriculture (USDA) told Reuters on Friday that "in the interest of leaving no stone unturned in the fight against HPAI, USDA continues to research vaccine options that can protect poultry from this persistent threat".

However, it still considers biosecurity measures to be the most effective tool for mitigating the virus in commercial flocks, it said in emailed answers.

The risk to humans from avian influenza remains low but countries must prepare for any change in the status quo, the World Health Organization has said.

Eloit said vaccination should focus on free-range poultry, mainly ducks, since avian influenza is transmitted by infected migrating wild birds. Vaccinating broilers, which account for about 60% of globalpoultry output, makes less sense, she said.

The H5N1 strain that has been prevalent in the current HPAI outbreak has been detected in a larger number of mammals and killed thousands of them, including sea lions, foxes, otters and cats.

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