It comes as the US deals with an H5N1 outbreak in dairy cattle that has seen the virus spread from mammals to humans for the first time.
The first lab-confirmed human case of H5N2 bird flu has died, according to the World Health Organisation
It said the 59-year-old Mexican resident developed a fever, shortness of breath, nausea and diarrhoea. They died on 24 April.
It’s the first confirmed human case of this bird flu sub-type in the world – and the first H5 infection reported in Mexico.
The victim had no history of exposure to poultry or animals, the WHO said.
However, they had multiple underlying health conditions and had been in bed for three weeks for other reasons before the bird flu symptoms took hold.
Before the H5N2 case was confirmed, it was unclear whether it could infect humans.
Avian flu viruses generally do not infect humans – but there are rare cases of it.
The H5N1, H7N9 and H5N6 subtypes have been responsible for most human infections to date, according to the US Centers of Disease Control and Prevention (CDC).
It said infections have ranged in seriousness; from no symptoms to mild illness, to severe cases that have caused death.
Birds shed the virus via faeces, mucous and saliva – and human cases can occur when it gets into the eyes, mouth or nose.
Human-to-human transmission is extremely rare, according to the CDC, and instances of it have only spread to a few people.
However, monitoring avian flu is important in case it mutates and gains the ability to spread more easily to – and among- humans.
Outbreaks often result in mass culls of birds to try to stop the infection spreading.
Australia’s Victoria state has recently detected the H7N3 strain at three farms, and the H7N9 strain at a fourth farm, with hundreds of thousands of birds to be killed.