First Documented Human Fatality from H5N2 Bird Flu Reported by WHO
The World Health Organization (WHO) has reported the first known human death from the H5N2 strain of bird flu in Mexico. The 59-year-old man, hospitalized in Mexico City, died on April 24 after experiencing fever, diarrhea, nausea, shortness of breath, and general discomfort. The WHO announced this on Wednesday, June 5, stating that the source of infection remains unclear, though H5N2 has been found in Mexican poultry.
No human-to-human transmission detected
Mexico’s health ministry confirmed no evidence of human-to-human transmission in this case. The deceased had several underlying health conditions, and all individuals who had contact with him tested negative for the virus. The risk to the general population is currently deemed low, according to the UN agency.
Recent outbreaks and global context
In March, Mexico reported an H5N2 outbreak in an isolated family unit in Michoacan state but assured it posed no risk to distant commercial farms or human health. Following the April death, Mexican authorities confirmed the presence of the virus and notified the WHO. Although there were three H5N2 outbreaks in nearby regions in March, no direct link to the human case has been established.
The H5N2 outbreak is distinct from the H5N1 outbreak in the US, which has infected three workers so far. Historically, other bird flu strains have caused human fatalities, including 18 deaths in China from H5N6 in 2021, according to the US Centers for Disease Control and Prevention.
Persistent threat of Avian influenza
Andrew Pekosz, an influenza expert at Johns Hopkins, emphasized the persistent threat of H5 viruses to mammals, noting their ability to infect mammals since 1997. He warned that each spillover is an opportunity for the virus to adapt and potentially become more transmissible to humans. Many bird flu cases have been identified in mammals such as seals, raccoons, bears, and cattle, primarily due to contact with infected birds.
