Which disease has been identified as a potential PHEIC due to its capacity for international spread?

Human influenza, particularly new subtypes, has been identified as a potential Public Health Emergency of International Concern (PHEIC) primarily due to its ability to rapidly spread across borders and affect populations worldwide. The World Health Organization (WHO) recognizes that new strains of the influenza virus can lead to significant outbreaks that may affect a large number of people, thereby posing a risk to public health on a global scale.

This designation is based on factors such as the virus's transmissibility, severity of disease, and the potential impact on public health systems. The capacity for international spread is a crucial consideration when determining whether a health issue qualifies as a PHEIC. In contrast, while measles is highly contagious and can spread internationally, it does not have the same potential for rapid emergence of new subtypes that can lead to widespread outbreaks. Hepatitis viruses typically have a more limited transmission scope compared to influenza, and norovirus, while significant in outbreaks, does not have the same capacity for persistent international spread or the severe health impacts associated with new influenza subtypes.