By Natalia Rueda 
The World Health Organization (WHO) has reported the first confirmed case of H5N2 bird flu in a human. The patient, Ismael Cosío Villegas, 59, died a week after being admitted to a hospital in Mexico City with symptoms including fever, respiratory distress and diarrhea. Notably, Villegas had not been exposed to infected poultry or animals, but had underlying illnesses.
Villegas’ death has prompted an urgent investigation by Mexican authorities to determine the source of the virus. Although close contacts of the deceased tested negative for the virus, the incident underscores the need for intensified surveillance and monitoring to prevent future outbreaks.
H5N2 is a different strain of bird flu than H5N1, the virus responsible for recent outbreaks in U.S. dairy cows. Experts are still studying the differences between these strains and their respective risks to human health. For the time being, WHO has assured the public that the risk of transmission remains low. However, this case has highlighted the critical importance of strong surveillance systems for both animals and humans.
Human-to-human transmission of bird flu is rare, and its patterns are still under investigation by health authorities. This flu can appear between two and seven days after infection. The most common symptoms are cough, fever, sore throat, muscle aches, headache, respiratory difficulties, nausea, vomiting and diarrhea.