The H5N1 chicken flu virus pressure has been detected in very excessive concentrations in uncooked milk from contaminated animals, the WHO mentioned on Friday, although how lengthy the virus can survive in milk is unknown.
Avian influenza A(H5N1) first emerged in 1996, however since 2020, the variety of outbreaks in birds has grown exponentially, alongside a rise within the variety of contaminated mammals.
The pressure has led to the deaths of tens of hundreds of thousands of poultry, with wild birds and land and marine mammals additionally contaminated.
Cows and goats joined the record final month – a shocking growth for specialists as a result of they weren’t regarded as prone to this sort of influenza.
US authorities earlier this month mentioned a person engaged on a dairy farm in Texas was recovering from chicken flu after being uncovered to cattle.
“The case in Texas is the first case of a human infected by avian influenza by a cow,” mentioned Wenqing Zhang, head of the worldwide influenza programme on the World Health Organization.
“Bird-to-cow, cow-to-cow and cow-to-bird transmission have also been registered during these current outbreaks, which suggest that the virus may have found other routes of transition than we previously understood,” she instructed a media briefing in Geneva.
It was solely the second case of a human testing constructive for chicken flu within the United States, and got here after the virus sickened herds that have been apparently uncovered to wild birds.
US data second-ever human chicken flu case, issues over international pressure
US data second-ever human chicken flu case, issues over international pressure
“Now we see multiple herds of cows affected in an increasing number of US states, which shows a further step of the virus spillover to mammals,” Zhang mentioned. “The virus has also been detected in milk from infected animals.”
Zhang mentioned there was a “very high virus concentration in raw milk”, however specialists have been nonetheless investigating precisely how lengthy the virus is ready to survive in milk.
The Texas well being division has mentioned the cattle infections don’t current a priority for the industrial milk provide, as dairies are required to destroy milk from sick cows. Pasteurisation additionally kills the virus.
“It is important for people to ensure safe food practices, including consuming only pasteurised milk and milk products,” Zhang mentioned.
From 2003 to April 1 this yr, the WHO mentioned it had recorded 463 deaths from 889 human instances throughout 23 nations, placing the case fatality price at 52 per cent.
Zhang famous that the human instances recorded in Europe and the United States up to now few years – for the reason that virus surged – have been gentle instances.
So far, there is no such thing as a proof that A(H5N1) is spreading between people.
And Zhang pressured that the A(H5N1) viruses recognized in cows and within the human case in Texas confirmed no elevated adaptation to mammals.
WHO says human instances of chicken flu ‘an enormous concern’
WHO says human instances of chicken flu ‘an enormous concern’
As for potential vaccines, if required, Zhang mentioned there have been some within the pipeline.
“Having candidate vaccine viruses ready allows us to be prepared to quickly produce vaccines for humans, if this becomes necessary,” she mentioned.
“For this particular H5N1 virus detected in dairy cows, there are a couple of candidate vaccine viruses available.”
In the case of a pandemic, there are shut to twenty influenza vaccines licensed for pandemic use they usually could possibly be tailor-made with the particular virus pressure in circulation, she mentioned.