Dairy cattle in the US have caught bird flu (Picture: Getty)
A person has caught bird flu from infected dairy cows in the US – the first time a human has caught the virus from another mammal.
The news comes after cattle in five US states – Texas, Kansas, Idaho, Michigan and New Mexico – tested positive for the H5N1 virus, which has swept the globe in recent years.
The US Centers for Disease Control (CDC) confirmed the case on Monday, but said the patient’s only symptom was eye inflammation. They are being treated with antiviral drugs and are expected to make a full recovery.
A statement from the CDC said: ‘This infection does not change the H5N1 bird flu human health risk assessment for the US general public, which CDC considers to be low.’
Only in very rare cases has bird flu spread from person to person, with no evidence of sustained transmission. However, many scientists are concerned by the spread of the disease from birds to a variety of other species.
The discovery last week of infected dairy cattle was the first case of the disease in cows. However, the US Department of Agriculture (USDA) stressed that the country’s milk supply is safe.
Bird flu: Key numbers
882 Cases of bird flu in humans between January 1 and December 21, 2023 across 23 countries
461 Fatalities during the same time
48 The number of different mammal species from which individuals have died from the virus since 2020, including polar bears, dolphins and seals
500,000,000 The number of domestic bird that have died or been killed as a result of the recent outbreak
75% The percentage of UK great skuas killed after becoming infected
‘At this stage, there is no concern about the safety of the commercial milk supply or that this circumstance poses a risk to consumer health,’ the USDA said in a statement.
The virus seems to be affecting older dairy cows, causing a drop in milk production and loss of appetite.
Dairy farmers in Texas became concerned about four weeks ago when their herds fell ill with a ‘mystery cattle disease’.
Most cases in humans occur from close contact with domestic poultry (Picture: Getty)
Texas Department of Agriculture commissioner Sid Miller said: ‘We hadn’t seen anything like it before.
‘It was kind of like they had a cold.’
The cows appeared to recover on their own within seven to 10 days, and the USDA confirmed that milk from sick cows is not allowed to be sold.
Bird flu: the lowdown
It is usually caught by close contact with infected birds
You can’t catch bird flu through eating fully cooked poultry or eggs, even in areas with an outbreak of bird flu
There is no bird flu vaccine
Bird flu has also been found in foxes, otters, dolphins, porpoises, skunks and a polar bear
This particular strain of bird flu was first discovered in China in 1997. Although largely confined to southeast Asia for many years, since 2020 it has spread across every continent except Oceania, resulting in the deaths of millions of birds and infecting dozens of non-avian species.
In January, a polar bear in Alaska died of the disease, the first known case in its species. Other mammals to have caught the disease include brown and black bear, lynx, foxes and mountain lions.
Sea animals have also been infected, including dolphins, porpoises and sea lions.
However, while the disease has a high fatality in humans, cases remain very rare. Those infected generally work closely with infected birds.