Mexico man's death linked to bird flu not yet seen in humans: WHO

Geneva (Switzerland), June 6 : A 59-year-old man in Mexico City who contracted a subtype of bird flu has died in Mexico City, the World Health Organization said.
The man, who had prior health complications died in hospital on April 24 after developing a fever, shortness of breath, diarrhoea, nausea and general discomfort, World Health Organization said in a statement on Wednesday, local time.
This marks the first laboratory-confirmed human case of infection with an influenza A (H5N2) virus reported globally and the first avian H5 virus infection in a person reported in Mexico, the WHO said.
"Although the source of exposure to the virus in this case is currently unknown, A (H5N2) viruses have been reported in poultry in Mexico," the WHO said.
The global health body said that the current risk to the general population posed by this virus is low.
The patient had no history of exposure to poultry or other animals but had had multiple underlying medical conditions and was bedridden for three weeks, for other reasons, prior to the onset of acute symptoms, the WHO said.
The health agency said it's not been possible to establish whether this human case is related to the recent poultry outbreaks.
In March 2024, a high pathogenicity avian influenza A(H5N2) outbreak was detected in a backyard poultry farm in the state of Michoacan, which borders the State of Mexico where the patient was residing.
Additionally, in March 2024, an outbreak of low pathogenicity avian influenza (LPAI) A(H5N2) was identified in poultry in Texcoco, State of Mexico, and a second outbreak of LPAI A(H5N2) in April in the municipality of Temascalapa in the same state. Thus far, it has not been possible to establish if this human case is related to the recent poultry outbreaks.
Australia's first human case of A (H5N1) infection was reported in May, but there were no signs of transmission.
The first detection of the H7 HPAI strain was confirmed on May 22 this year at a poultry farm near Meredith, Victoria. On May 24, Agriculture Victoria's tracing activities identified a separate H7 HPAI strain on a poultry farm near Terang. On June 3 ,H7 HPAI was confirmed at a third Victorian poultry farm.
"Avian influenza virus has been confirmed at a fourth Victorian poultry farm," the Australian government said in a statement on Wednesday as cited by Reuters.
Meanwhile, in the US, an outbreak of the H5N1 strain of the bird flu first reported in US poultry farms in the year 2022 in millions of birds as well as older dairy cows has spread to three farmworkers -one in Texas and two in Michigan.
According to the US Centers for Disease Control and Prevention (CDC), There is no evidence of human-to-human transmission and the risk to the general public is low.
ABC News cited Dr. John Brownstein, an epidemiologist and chief innovation office at Boston Children's Hospital as explaining that "while both H5N2 and H5N1 belong to the same family of influenza A viruses, H5N1 has been known to infect humans for years, whereas this is the first-ever reported case of H5N2 in humans."
"The good news is that neither H5N2 nor H5N1 have demonstrated human-to-human transmission so far. However, this first case is a wake-up call. It reminds us that influenza viruses can evolve, and continued surveillance of these viruses in both animals and humans is crucial," he told ABC News.
Animal influenza viruses normally circulate in animals but can also infect humans.
Infections in humans have primarily been acquired through direct contact with infected animals or contaminated environments.
Depending on the original host, influenza A viruses can be classified as avian influenza, swine influenza, or other types of animal influenza viruses.
Avian influenza virus infections in humans may cause mild to severe upper respiratory tract infections and can be fatal. Conjunctivitis, gastrointestinal symptoms, encephalitis and encephalopathy have also been reported.
Laboratory tests are required to diagnose human infection with influenza, the WHO said.