(Geneva) A first human case of avian influenza type H5N2, a different strain from that linked to the current epidemic in cows in the United States, has been detected in Mexico, the WHO announced on Wednesday.

“This is the first laboratory-confirmed human case of influenza A(H5N2) virus infection reported in the world and the first avian H5 virus infection in a person reported in Mexico,” said l World Health Organization in an epidemiological bulletin.

The WHO explains that how the person was contaminated is “currently unknown”, but emphasizes that cases of H5N2 “in poultry have been reported in Mexico”.

On May 23, Mexican health authorities reported to WHO a confirmed case of human infection with the H5N2 virus in a 59-year-old person who was hospitalized in the Mexican capital and had no contact with poultry or other animals.

WHO does not specify whether it is a man or a woman.

The person was already suffering from multiple health problems, and had developed a fever, shortness of breath, diarrhea, nausea and general malaise on April 17, before passing away on April 24.  

In addition, other cases of H5N2 were identified in poultry in March in Texcoco, in the state of Mexico, and in April in the municipality of Temascalapa, in the same state. 

“So far, it has not been possible to establish” whether the reported human case is linked to these recent cases in poultry, says the WHO.

An outbreak of avian flu of the H5N1 strain has spread for several weeks in dairy cow herds in the United States. A few human cases have been reported, but no human-to-human contact.