The entire global scientific community is holding its breath. In April 2022, they announced their first-ever detection of the H5N1 bird flu strain in a sheep in the UK. The virus was identified in a single ewe in Yorkshire, marking the first instance of H5N1 being found in sheep worldwide. It was Christine Middlemiss, the UK’s Chief Veterinary Officer who announced the detection of the virus. This came after months of positive tests on milk that showed its spread.
For now, experts are watching the developments very closely. They’ve been wary, pointing to instances of H5N1 being detected in other mammals, including dairy cows, felines, canines, dolphins, seals, and tigers. This evolution increases worries about the virus jumping to additional mammalian hosts and geographic areas.
Implications for Human and Animal Health
Over the last year, international outbreaks suggest there have been at least 60 instances of human infection with H5N1. Unfortunately, the overwhelming majority of these examples have taken place in the US. In humans, cases have ranged from asymptomatic infections to a few deaths. This latest finding, that H5N1 has now been found in sheep, showcases the virus’s capability and potential to spillover into various animal species.
Christine Middlemiss reassured the public regarding the current situation:
"No further infection with avian influenza virus was detected in the remaining flock and this remains a single case in a mammal detected on the premises."
Even with this assurance, scientists are calling for increased caution and preparedness to stop its further spread.
Australia's Unique Position and Challenges
At this time, Australia is the only continent that is completely unaffected by the H5N1 strain of avian influenza. Previous outbreaks of H7 avian influenza subtypes have caused enormous devastation to the poultry industry. They accounted for an unprecedented loss of more than 10 percent in the laying hen flock. The imminent arrival of H5N1 threatens Australia’s $5 billion sheep industry and its unique wildlife.
Kirsty Short, a leading scientist, highlighted the urgency of taking proactive measures:
"We are incredibly fortunate that we don't have this virus in Australia yet."
With concerns over native species, Short added:
"If this virus becomes established in Australia we could lose a large number of native birds and potentially mammals as well."
Call for Government Action
Australian scientists are calling on the federal government to invest more in protecting Australia’s sheep industry from a growing feral threat. They caution that an H5N1 eruption could be devastating both agriculturally and ecologically. Another danger posed by highly pathogenic avian influenza strains, including H5N1, could wipe out native species, including black swans.
Kirsty Short emphasized the importance of research and preparedness:
"We need to do more research about getting prepared for this virus, and one of the things I am particularly concerned about is our native species."
The potential for H5N1 to arrive in Australia has heightened concerns for impacts to agricultural interests and ecological integrity.
