First human case of bird flu strain H5N2 claims life in Mexico

A 59-year-old man in Mexico has died from the first known human case of the H5N2 bird flu strain, according to the World Health Organization (WHO). The man, hospitalized in Mexico City, succumbed to the illness on April 24 after experiencing fever, shortness of breath, diarrhea, nausea, and general discomfort.

The WHO reported on Wednesday that the source of the man's infection remains unclear, though H5N2 has been detected in poultry within Mexico. Despite this, the UN agency assured that the current risk of the virus spreading to the general population is low.

Mexico's health ministry confirmed there has been no evidence of person-to-person transmission in this case. The deceased had several preexisting health conditions, and all individuals who had contact with him tested negative for the virus.

In March, an isolated outbreak of H5N2 was reported in a family unit in Michoacan state, but authorities at the time stated it posed no threat to commercial farms or human health. Following the man's death in April, Mexican authorities verified the virus's presence and informed the WHO.

Scientists are vigilant for any changes in the virus that might enhance its ability to spread among humans. Andrew Pekosz, an influenza expert at Johns Hopkins University, emphasized the need for close monitoring, noting that H5 viruses have shown a consistent tendency to infect mammals since 1997.

Other strains of bird flu have also been responsible for human fatalities globally. The CDC documented that H5N6 killed 18 people in China during a 2021 outbreak. The H5N1 strain recently infected three dairy farm workers in the United States.

Cases of bird flu in mammals have been observed due to contact with infected birds, with instances reported in seals, raccoons, bears, and cattle. In May, Australia reported its first human case of A(H5N1) without signs of transmission but found more poultry cases of H7 bird flu in Victoria.