Image copyright Getty Images Image caption The new variant is a ret-RNA, or less well understood replication gene
Six countries have been added to England’s ‘risk list’ of countries at “significant risk” of spread of the avian flu virus .
The government statement includes those from countries in Europe, Russia, Vietnam, China, Ukraine and the US.
The ‘risk’ classification is another step towards banning imports of livestock or food from affected countries.
Two new flu strains have emerged since the original strain was identified.
Before Friday the countries on the government’s website were India, Indonesia, Thailand, Kazakhstan, Cameroon, Somalia, Cameroon, Laos, and Egypt.
More now on our trip blog .
Over two million birds have already died in the current outbreak of bird flu, which has been raging since November.
“This new variant is the most serious one we’ve seen so far”, virologist Professor Jexson Jamail, from Oxford University, told BBC News.
The US Centers for Disease Control and Prevention warned that two new avian flu strains – a member of the H5N1 strain and a new variant – were “urgently spreading” throughout China and Vietnam.
An American chicken plant was also being shut down on the advice of the USDA after the first confirmed outbreak on 24 June .
It is important to note that this new H5N1 strain is not of the same species as bird flu viruses in China that are spread through live chickens and other poultry .
“I think it is highly likely that this new H5N1 virus will reach the US eventually” given the vast amount of imported poultry from China, he said.
The UK’s Centre for Veterinary Studies said there were three new strains to be concerned about : The first is a coronavirus known as La Crosse-Oligovirus type 2, commonly called “bird flu” and it can cause coughs and fever in humans .
The second is a ret-RNA, or less well understood replication gene from avian flu that is being transmitted from person to person .
The third is an S3/Asia strain of avian flu and has been circulating through birds in Viet Nam , Indonesia and Taiwan since the beginning of the year.
It has not spread to humans and has not caused cases of pneumonia, the UK statement said.
The US Department of Agriculture said it had contacted chicken producers in China and the Asia-Pacific region to warn them about this new virus.
The agency is also working with other countries with exporting poultry in the region to encourage more common safeguards and educate them about the virus.
Meanwhile the World Organisation for Animal Health (OIE) says production has been halted or interrupting in 30 countries , mainly in China and Vietnam.
Read the full statement from UK agriculture secretary Michael Gove .
The UK’s Department for Environment, Food and Rural Affairs (Defra) said this summer’s “egg imports into England and Wales have remained at levels seen in recent years”.
If the reports of bird flu outbreaks are true, this is a new mutated strain of virus. — David Cameron (@David_Cameron) July 7, 2018
The London School of Hygiene and Tropical Medicine explained in a statement that unlike the H5N1 strain which can spread from chickens to humans, this new bird flu is more like a virus that travels by moving between humans, and this can be fatal.
This virus also has a mutation that allows it to survive longer in chickens but doesn’t affect humans, said a statement from its Professor Daniel Su.
As far as we are aware, it is unlike any other virus circulating around the world. https://t.co/ru7XBTJKLy — BOAT (@BOATsearching) July 5, 2018
The analyst from the department has said the new version is unique and looks like a red herring so we will have to wait and see how it spreads.
The Russian embassy in London said it had received no notice of an embargo from the UK government but still advised everyone to take precautions to avoid contact with wild birds.
What we know so far
29 June : Over 300,000 chickens and ducks slaughtered
29 June : Over 300,000 chickens and ducks slaughtered 20 July : 2,500 people sickened
6 June : Scans of 108,000 dead chickens in Hebei province and 50,000 poultry in Shanghai confirmed
6 June : Scans of 108,000 dead chickens in Hebei province and 50,000 poultry in Shanghai confirmed 19 July : Deaths reported
8 June : Outbreak blamed on H5N8 bird flu; bird