Public Health Risk Assessment associated with the spread of zoonotic avian influenza A(H5N1) clade 2.3.4.4b in the Region of the Americas - 12 July 2024

The purpose of this regional rapid risk assessment (RRA) is to assess the current public health risk to human health associated with the introduction and expansion of zoonotic avian influenza A(H5N1) clade 2.3.4.4b in mammals species in the Region of the Americas. The RRA has been conducted taking into account the following criteria: (i) the risk of virus dissemination, specifically the potential occurrence in further countries in North America, Central America, South America, and in the Caribbean of events in dairy cattle and related spillovers to other mammals; (ii) the risk to human health including the risk of human exposure to infected animals and contaminated environments, the potential worsening of clinical and epidemiological characteristics of the disease if the virus further adapts to humans and/or other mammals, the potential for increased mammalian susceptibility from genomic mutations and viral reassortment, as well as risk factors for the occurrence of human infections and determinants related to outbreaks in animals; and (iii) the risk to public health based on the varying levels of capacities for early detection, prevention, and response with a One Health approach within the region, as well as the challenges in the implementation and adaptation of control measures (encompassing response capabilities, surveillance, diagnostic techniques, health and animal service preparedness, and medical supplies with available resources).