Second human avian flu case linked to infected cattle
Avian influenza has been confirmed in more than 60 herds in the USA.
Health officials in the USA have confirmed a second human case of highly pathogenic avian influenza (H5N1) linked to the ongoing outbreak of the virus in dairy cattle.
The patient, a farm worker in Michigan who was being monitored after exposure to infected cattle, only reported mild eye symptoms and has recovered. An eye swab from the patient tested positive for the virus, although a nasal sample tested negative.
The case is similar to one in Texas in late March in which a dairy worker also tested positive after exposure to infected cattle and experienced mild eye symptoms. The earlier case is believed to have been the first reported instance of the H5N1 virus being transmitted from a mammal to a human.
A previous human case in 2022, in which a farm worker from Colorado tested positive for the virus, was linked to exposure from infected poultry.
The outbreak of the virus among dairy cattle in the USA has so far spread to nine states and affected more than 60 herds. Mandatory testing has been introduced for cattle being moved between states.
There is currently no evidence to suggest that the virus is spreading between humans.
Natasha Bagdasarian, Michigan’s chief medical executive, said: “The current health risk to the general public remains low.
“This virus is being closely monitored, and we have not seen signs of sustained human-to-human transmission at this point. This is exactly how public health is meant to work, in early detection and monitoring of new and emerging illnesses.”
Although no cases of the virus have been detected in cattle in the UK, the Animal and Plant Health Agency recently updated its case definition and diagnostic testing criteria for highly pathogenic avian influenza (H5N1) in mammals to include cattle, sheep, goats and pigs.
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