A PHEIC is defined by WHO as "an extraordinary event which is determined to constitute a public health risk to other States through the international spread of disease and to potentially require a coordinated international response" under International Health Regulations, with recent examples including COVID-19, mpox (fka monkeypox), and wild polio (International Health Regulations 2005, linked here under publications - WHO - International Health Regulations, International Health Regulations - Annex II, Pan American Health Organization, WHO - 20 January 2025, Johns Hopkins). The question is concerned with a PHEIC declared regarding an influenza virus classified as H5N1 or a contemporary descendant. If WHO declares a PHEIC for a mutated type of influenza formed through "reassortment/recombination" with H5N1, then it will count (CDC - Types of Influenza Viruses, CBS News, Newsweek, Nature). For the purposes of this question, a descendant will be considered contemporary if WHO reports that the "reassortment/recombination" is suspected to have occurred since 2020 (CDC).

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