A new strain of bird flu has jumped to humans in an event that has ‘potential for high public health impact’, the World Health Organization has warned.
Officials say a 59-year-old man in Mexico died after battling a seven-day illness that left him suffering from fever, shortness of breath, diarrhea and nausea.
Testing showed they were infected with H5N2, marking the first time this strain has ever been detected in humans. It differs from the H5N1 strain behind the outbreak in cattle and that has sickened three people in the US this year.
The patient had no history of exposure to poultry or other animals, with it being unclear how he became infected.
But officials said the risk to the public is ‘low’, saying the patient had underlying health conditions. It was not clear whether the disease had been spread to others.
They warned in an alert released today, however, that ‘a human infection caused by a novel [bird flu virus] is an event that has the potential for high public health impact’.
The patient, from Mexico City, became unwell on April 17, but waited a week before seeking help in hospital.
He died on the same day as his admission, however, because of the ‘complications of his condition’.
PCR tests carried out on April 24 revealed he had been infected with a flu virus, with later testing confirming the patient had H5N2.
Officials have tested 17 people who came in close contact with the patient at the hospital, including one person who reported a runny nose. All tested negative.
Twelve people who lived near the patient’s home in Mexico City — including seven with symptoms of illness — were also tested for bird flu, although all tested negative.
Officials are now carrying out blood tests to screen for antibodies against the virus, which would reveal whether any had a previous infection.
The source of the infection is yet to be determined, although several flocks of poultry — which can carry H5N2 — have recently tested positive for the virus.
H5N2 was first detected in poultry in the 1990s, and has also been detected in other animals including pigs — bringing it a step closer to infecting humans.
It is not the strain that is causing a ‘pandemic’ in the animal world, with this being H5N1 which has been detected in everything from foxes to raccoons, skunks, cows, seals and deer.
The strain emerged after a version of bird flu that infects wild birds and one that infects domestic birds met in a cell and swapped genes.
