Avian Influenza A(H5N1) - Mexico

On 2 April 2025, the International Health Regulations (IHR) National Focal Point (NFP) for Mexico notified the World Health Organization (WHO) of the country’s first laboratory-confirmed human infection with an avian influenza A(H5N1) virus in the state of Durango. In response, local and national health authorities have implemented a range of measures to monitor, prevent, and control the situation. 

There have been reports of A(H5N1) outbreaks in birds in Durango, although the exact source of infection in this case remains under investigation. To date, no further cases of human infection with influenza A(H5N1) linked to this case have been identified. In accordance with the IHR (2005), any human infection caused by a new influenza A virus subtype is considered a potentially significant public health event and is subject to mandatory notification to WHO. 

Based on the information currently available on this and previous cases, WHO assesses the risk to the general population posed by A(H5N1) viruses as low. For individuals with occupational exposure to these viruses, the risk of infection is considered low to moderate. The situation may change as more information is gathered and so WHO continues to closely monitor these viruses and the global epidemiological situation.