Bird flu is expanding into new territories and increasingly crossing species barriers, causing concern among scientists and medical experts. The infection is found not only among domestic and wild birds, but also in animals that have not previously been associated with the virus — in particular, penguins in the Antarctic and camels in the Middle East. In some cases, human infection has also been recorded.
For data The BBC, experts are sounding the alarm over the spread of the highly contagious H5N1 strain, which has covered almost every continent except Australasia. In the US, according to statistics from the Ministry of Agriculture, the virus has been recorded in all 50 states, both among domestic birds and among wild birds. More than a thousand heads of cattle are also known to be infected.
There have already been at least 70 confirmed cases of infection in humans, one of which has been fatal. At the same time, epidemiologists emphasize that the true scale of infection may be much larger, since official statistics significantly underestimate real indicators.
Professor Caitlin Rivers from Johns Hopkins University believes that the moment to contain the spread of the virus may have already been lost due to the uncoordinated actions of the US authorities. She points out that the lack of uniform rules for transporting animals in different states contributes to the epidemic risk. She is supported by Professor Kamran Khan of the University of Toronto, emphasizing that the long circulation of the virus in mammals could be the starting point for a new pandemic.
According to the World Organization for Animal Health, in April 2025, there were 59 outbreaks of bird flu among domestic birds and 44 among wild birds and mammals in different regions of the world. Since December 2024, cases of human infection have been recorded in the USA, Great Britain, India, Mexico, Cambodia and Vietnam.
Although the H5N1 virus was rarely transmitted to humans in the past, now, according to Professor Rivers, the frequency of interspecies transmission is increasing, which increases the threat of adaptation of the pathogen to the human body. She warns: if measures are not taken to contain the infection, this could lead to a sudden mutation of the virus with a much higher threat to humanity.
