An ongoing outbreak of a deadly avian flu strain is becoming a greater cause for concern for experts as it spreads among mammalian species - but New Zealand health authorities say we are "well-positioned" to respond if needed.
The current outbreak of bird flu is ravaging bird populations around the world and is spilling over into mammals, HuffPost reported.
The US Department of Agriculture said the highly pathogenic H5N1 avian flu had been detected in mammals such as skunks, bears, raccoons, and red foxes.
Meanwhile, in the United Kingdom, the Animal and Plant Health Agency found positive cases in foxes and otters. They also said a cat tested positive in France and there's a large bird flu outbreak in Spain at a mink farm.
Aoteaora's Ministry of Health (MoH) told Newshub avian influenza is typically transmitted from birds to humans and is "usually sporadic and happens in specific contexts".
"People who are in close and repeated contact with infected birds or heavily contaminated environments are at risk for acquiring avian influenza," a MoH spokesperson said.
The spokesperson said there were two human cases detected globally in 2022, one case in the UK and another in the US.
"H5N1 and other avian influenza viruses do not efficiently transmit from person to person."
The World Health Organization (WHO) reported 868 cases of human infection from January 2003 to November 2022.
The virus has been reported globally from 21 countries and the MoH spokesperson said of the 868 cases, 457 of them were fatal.
How is bird flu being transmitted among mammals?
Expert Jürgen Richt, a professor and director of the Center on Emerging and Zoonotic Infectious Diseases at Kansas State University, told USA Today that most of these infections in mammals are likely independent cases where an animal eats an infected bird.
Although he warns the outbreak at the Spanish mink farm may be a case of the virus transmitting from mammal to mammal.
For the United States, their Centers for Disease Control and Prevention said bird flu remains an animal health issue. There have only been four human infections reported there.
New Zealand has never had a case of bird flu.
What does it mean for humans?
While more research is needed into how bird flu is spreading, it doesn't look too good for people.
"If this virus has mammalian adaption and can transmit between mammals, humans are immunologically naive … and humans are mammals," Richt told USA Today.
Aotearoa's surveillance and plan for bird flu
The MoH spokesperson said the Institute of Environmental Science and Research (ESR) operates acute respiratory illness surveillance in hospital and community settings across Aotearoa.
"Together, these surveillance systems provide a robust understanding of the burden of disease due to respiratory viruses. The systems are also designed to provide for early detection of non-seasonal influenza viruses such as Influenza H5N1," the spokesperson said.
"In addition to the acute respiratory illness surveillance systems in operation, Influenza H5N1 is notifiable in New Zealand as a highly pathogenic avian influenza."
MoH said alerts of a public health risk could include several reports of virus infections in people from exposure to birds, or identification of spread from one infected person to a close contact locally or internationally.
Interim director of outbreak response at Te Whatu Ora Matt Hannant said there has not been sustained human-to-human transmission of H5N1, "which means the risk to public health is currently considered to be low".
Hannant said Te Whatu Ora is "well positioned" to respond if an infectious disease enters Aotearoa, adding the response would be guided by the country's influenza pandemic plan.
"Te Whatu Ora has significant experience in managing diseases transmitted by the respiratory route through responding to COVID-19."
Hannant said Te Whatu Ora reports cases of notifiable infectious diseases to MoH, "activating public health plans and assessment reviews when necessary, and delivering vaccinations if this is required".
