WHO Warns of Increasing Risk of Bird Flu Spreading to Humans

A senior World Health Organization (WHO) official has issued a stark warning about the increasing risk of human-to-human transmission of bird flu. Despite no current evidence of direct transmission between people, there are concerns that the virus, which has evolved to infect humans from other mammals, could mutate further and pose a serious threat.

Jeremy Farrar, WHO’s chief scientist, highlighted the gravity of the situation during a recent press briefing. He emphasized the virus’s high mortality rate in humans and the alarming rise in cases of H5N1 bird flu, which has led to 888 reported human infections, with 52% proving fatal, between January 2003 and March 28, 2024.

The global outbreak, which began in 2020 following a resurgence in Europe, has caused widespread deaths among birds and is now affecting mammals like cows. This development is particularly concerning, as cows share similar body structures with humans, raising fears of potential human-to-human transmission.

While there have been no documented cases of human-to-human transmission, Farrar stressed the importance of vigilance, noting that the virus’s increased spread over the past two years has elevated it to the status of a “global zoonotic animal pandemic.” Efforts are underway to ensure equitable access to vaccines, therapeutics, and diagnostics in case of human transmission.

Despite the current lack of evidence supporting human-to-human transmission, concerns remain high due to the virus’s potential to mutate. Experts warn that the virus’s spread to cows, which are genetically closer to humans, and its high mortality rate make it a serious candidate for a future pandemic.

Recent outbreaks among cattle and goats in several U.S. states have raised further alarm, with reports of a man in Texas contracting bird flu after contact with an infected dairy cow. This marks the second case of H5N1 infection in humans in the U.S., following an earlier case in 2022.

While the FDA has approved vaccines for human use, current supplies are limited. In the event of a pandemic, plans are in place to ramp up production, but this process could take at least six months to provide sufficient doses for the entire population.