From the article:

In March, Mexico's government reported an outbreak of A(H5N2) in an isolated family unit in the country's western Michoacan state. The government said the cases did not represent a risk to distant commercial farms, nor to human health.

After the April death, Mexican authorities confirmed the presence of the virus and reported the case to the WHO, the agency said.

This doesn't seem to be spreading very effectively, given these are the only known cases and it's already June.