WHO confirms first fatal human case of H5N2 bird flu

A person died of bird flu in Mexico in the first confirmed case of a human infected with the H5N2 variant, the World Health Organization said Wednesday.

The 59-year old, who died on April 24 after developing fever, shortness of breath, diarrhoea and nausea, had "no history of exposure to poultry or other animals" and "multiple underlying medical conditions", the WHO said in a statement.

The resident of the State of Mexico was hospitalised in Mexico City and died the same day, the statement said.

It was the "first laboratory-confirmed human case of infection with an influenza A(H5N2) virus reported globally", the WHO added.

Mexican health authorities reported the confirmed case to the UN health body on May 23 after conducting laboratory tests.

The source of exposure to the virus was unknown, the WHO said, although cases of H5N2 have been reported in poultry in Mexico.

H5N2 cases were detected in a backyard poultry farm in Michoacan state in March, with other outbreaks identified in the State of Mexico, according to the UN health body.

But it said establishing a link between the human case and the poultry infections was so far impossible, estimating the risk to people as "low".

Mexico's health ministry said in a statement that the person who died was "a 59-year-old man with a history of chronic kidney disease, type 2 diabetes, (and) long-standing systemic arterial hypertension".

"There is no risk of contagion for the population," the statement said, adding that "all samples from identified contacts (of the patient) have been negative".

Authorities are monitoring farms near the victim's home and have established a permanent monitoring system to detect other cases in wildlife in the area, the statement added.

A different variant of bird flu, H5N1, has been spreading for weeks among dairy cow herds in the United States, with a small number of cases reported among humans.

But none of the cases are human-to-human infections, with the disease instead jumping from cattle to people, authorities have said.