The World Health Organisation says a death was caused by the first laboratory-confirmed human case of infection with a subtype of avian influenza.

The WHO said the 59-year-old resident of Mexico had died on April 24 after developing a fever, shortness of breath, diarrhoea, nausea and general discomfort.

This was the first laboratory-confirmed human case of infection with A(H5N2) subtype of bird flu reported globally and the first H5 virus infection in a person reported in Mexico.

The victim had no history of exposure to poultry or other animals, the WHO said.

Cases of A(H5N2) subtype of avian influenza have been reported in poultry in Mexico.

The person had multiple underlying medical conditions and had been bedridden for three weeks, for other reasons, prior to the onset of acute symptoms, the world health agency said.