The World Health Organization (WHO) reported that a man died in Mexico from a strain of bird flu, H5N2, which has never before been detected in humans.

The WHO stated on Wednesday that it is unclear how the individual became infected. "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 organization said in a statement.

Scientists are on alert for changes in the virus that could indicate it is adapting to spread more easily among humans. However, the UN agency stated on Wednesday that the current risk of the bird flu virus to the general population in Mexico is low.

The WHO reported that a 59-year-old man, who had been hospitalized in Mexico City, died on April 24 after experiencing fever, shortness of breath, diarrhea, nausea, and general discomfort.

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No evidence of person-to-person transmission

Mexico’s Health Ministry stated on Wednesday that there is no evidence of person-to-person transmission of bird flu in the case of the deceased man, who had several pre-existing health conditions. All individuals who had contact with him have tested negative, the ministry added.

In March, Mexico's government reported an outbreak of A(H5N2) in an isolated family unit in the western state of Michoacan. However, they stated that it did not pose a risk to distant commercial farms or human health at that time.

Following the deadly case in April, Mexican authorities confirmed the presence of the virus and reported the case to the WHO, according to the agency.

In March, there were three poultry outbreaks of H5N2 in nearby parts of Mexico, but authorities have not been able to establish a connection to the April death.

Scientists stated that the case in Mexico is unrelated to the outbreak of a different strain of bird flu, H5N1, in the United States, which has so far infected three dairy farm workers. Other bird flu varieties have caused fatalities worldwide in previous years. For instance, during an outbreak of H5N6 in China in 2021, 18 people died, according to a timeline of bird flu outbreaks from the US Centers for Disease Control and Prevention.