A man has died after contracting a strain of bird flu never before detected in humans.
The man, from Washington, was older and had ‘underlying health issues’ before he contracted the H5N5 flu variant.
It’s the first reported bird flu case in the United States in nine months, and only the second reported death this year.
The Washington State Department of Health said in a statement: ‘The person had a backyard flock of mixed domestic birds.’
After testing the birds, the DOH found avian influenza, meaning the patient likely contracted it at home from his own flock.
So far, no one else close to the man has tested positive for the virus, and the Centres for Disease Control stressed that the risk remains low.
What are the symptoms of bird flu in humans, and how do they differ from other flu strains?
When humans contract bird flu, they can become extremely ill, just as they do when contracting a normal flu.
Symptoms can include fever, sore throat, cough, stuffy or runny nose, nausea, vomiting, fatigue, muscle aches, diarrhoea, shortness of breath and pink eye.
Bird flu is very rarely contagious, however, between humans. Those who work with poultry and other birds are at high risk of contracting it.
The incident in Washington came after an expert warned that the US and the world should be worried that bird flu could become the next pandemic.
H5N1 cases in humans who had contact with sick animals have been recorded in all 50 states, and the avian flu is widespread in wild birds worldwide.
Dr Robert Murphy, a professor of infectious diseases and biomedical engineering at Northwestern University, told Metro: ‘We have to (worry) because it could be another pandemic. It definitely could be.’
While the good news is there is no evidence of human-to-human H5N1 transmission to date, it is ‘a kind of virus that mutates very easily and frequently’, he said.
The Biomedical Advanced Research and Development Authority (BARDA) within the US Department of Health and Human Services, and similar agencies in other countries, have been stockpiling millions of doses of avian flu vaccines for humans.
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