Avian influenza in the Americas: animal outbreaks decline, but PAHO calls for continued vigilance

Although no human cases have been reported in the Region so far in 2026 and animal outbreaks have declined compared with the previous year, the virus continues to circulate among birds and mammals, underscoring the need to strengthen surveillance and coordination across the human, animal, and environmental health sectors.

Washington, D.C., 27 August 2026 (PAHO) - The Pan American Health Organization (PAHO) reported that avian influenza A(H5) continues to circulate in the Americas, although the number of animal outbreaks has decreased compared with the same period last year. The Organization urged countries to maintain and strengthen surveillance in both animals and humans to promptly detect any changes in the behavior of the virus.

According to a new PAHO epidemiological update, between January and 15 July 2026, 10 countries in the Region reported 455 outbreaks of avian influenza A(H5) in animals, including 386 outbreaks in birds and 69 in mammals. This represents a 25.7% decrease compared with the 612 outbreaks reported during the same period in 2025. The decline was particularly pronounced among mammals, where outbreaks dropped from 196 to 69, a reduction of nearly 65%.

The update also shows that, as of August 2026, no human cases of avian influenza A(H5) have been reported in the Americas this year. Between 2022 and the end of 2025, 75 human infections caused by A(H5) viruses were reported in five countries in the Region: Canada, Chile, Ecuador, Mexico, and the United States. The most recent human case in the Americas was reported in November 2025.

Globally, between 2003 and 7 August 2026, a total of 1,002 laboratory-confirmed human cases of avian influenza A(H5N1), one of the A(H5) virus subtypes, were reported in 25 countries, including 479 deaths. In 2026 alone, nine human cases, including two deaths, were reported worldwide.

The virus continues to circulate in animals around the world. Between October 2025 and July 2026, a significant increase in detections among wild birds was observed, particularly in Europe. In addition, new detections in Australia and New Zealand confirmed the geographic expansion of the virus into areas where it had not previously been identified.

Available scientific evidence indicates that sustained person-to-person transmission has not been demonstrated. Most human infections reported worldwide continue to be associated with direct or indirect exposure to infected animals or contaminated environments.

Nevertheless, the continued presence of the virus in wild birds, poultry, and mammals underscores the need for close surveillance. While the joint assessment by the Food and Agriculture Organization of the United Nations (FAO), the World Health Organization (WHO), and the World Organisation for Animal Health (WOAH) maintains that the global public health risk remains low, the risk is considered low to moderate for people with occupational or frequent exposure to potentially infected animals.

Key recommendations include strengthening surveillance among people at higher risk of exposure, such as poultry workers, veterinarians, laboratory personnel, and rural producers; enhancing biosecurity measures in animal production facilities; expanding genomic surveillance to promptly detect changes in the virus; and ensuring the rapid notification and investigation of new outbreaks or suspected cases.

In addition, PAHO recommends monitoring people exposed to infected animals for 14 days following their last exposure to identify symptoms consistent with the disease and enable early action if infections occur.

PAHO also reminded the public that there is no evidence that avian influenza is transmitted through the consumption of properly cooked poultry, eggs, or other poultry products. The Organization further reiterated the international recommendation to consume pasteurized milk to minimize potential risks associated with raw milk, consistent with general food safety recommendations.