The World Health Organization (WHO) on Wednesday confirmed the first fatal case of human infection with a strain of bird flu known as H5N2 in Mexico.

The 59-year-old man with multiple underlying medical conditions had been hospitalized in Mexico City after being infected with the H5N2 virus.

He died on April 24 after developing a fever, shortness of breath, diarrhoea, nausea and general malaise, the WHO said in a statement on Wednesday.

It is the first laboratory-confirmed case worldwide of human infection with the H5N2 strain of bird flu, also known as avian influenza.

It is also the first known avian H5 virus infection in a person in Mexico, according to the WHO.

“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.

In March, an outbreak of avian influenza was discovered on a small poultry farm in Michoacán, which borders the State of Mexico where the infected person lived.

The victim had no history of exposure to poultry or other animals and had multiple underlying medical conditions, with relatives reporting that the victim had already been bedridden for three weeks prior to the onset of acute symptoms, the WHO said.

“Based on available information, WHO assesses the current risk to the general population posed by this virus as low,” the WHO said.