Pandemic warning as new virus spreads in the US

The Global Virus Network, an organisation representing human and animal virologists from over 40 countries, have urged world governments to take action and be prepared against the H5N1 outbreak.


Calling for action in a LANCET report, the global organisation has said, "The recent emergence of highly pathogenic H5N1 avian influenza virus infections in dairy cows and humans in the U.S. has raised alarms regarding the potential for a pandemic. Over 995 dairy cow herds and at least 70 humans have been affected." "Concurrently, the virus continues to circulate in wild birds, backyard flocks, and hunted migratory species, further amplifying the risk to humans and domestic animals."


Why this bird flu matters to humans

The H5N1 virus, also known as avian influenza or bird flu, is a type of influenza virus that primarily affects birds but can occasionally infect humans and other animals. First identified in geese in China in 1996, H5N1 gained global attention after it started causing serious outbreaks among poultry and even jumped to humans in some cases. Although not easily transmitted between humans, its high mortality rate in human cases makes it a serious public health concern.


H5N1 is a subtype of the Influenza A virus. The “H” and “N” refer to proteins on the virus's surface—hemagglutinin (H) and neuraminidase (N). There are multiple subtypes (like H1N1 or H3N2), but H5N1 is among the most dangerous because of its ability to cause severe disease in both birds and humans.


It is considered a highly pathogenic avian influenza (HPAI) virus, meaning it spreads quickly and causes serious illness in birds. This makes it economically devastating for poultry industries and a challenge for food security in affected regions.


In birds, H5N1 spreads via saliva, nasal secretions, and feces. Domestic poultry like chickens and turkeys are especially vulnerable. Migratory wild birds can carry the virus over long distances, making it difficult to contain.


Humans usually get infected through direct or close contact with infected birds or their droppings. This can happen in live bird markets, farms, or when handling raw poultry without proper precautions. So far, sustained human-to-human transmission hasn't occurred, but experts warn that if the virus mutates to spread efficiently between people, it could spark a pandemic.


Symptoms in humans range from typical flu-like signs (fever, cough, sore throat) to severe respiratory illnesses like pneumonia and acute respiratory distress syndrome (ARDS). Some patients have also experienced diarrhea, encephalitis, and multi-organ failure.


"Co-circulation of H5N1 viruses with swine or human seasonal influenza viruses, especially during the Northern hemisphere winter season, could lead to reassortant viruses that can efficiently spread in humans," the LANCET report warns. The CDC currently considers the virus to have a moderate future pandemic risk when compared to other Influenza A viruses.