New World bats harbor diverse influenza A viruses. Researchers identified a novel influenza A virus, H18N11, in flat-faced fruit bats from Peru. Phylogenetic analysis showed that New World bats possess more influenza virus genetic diversity than all other mammalian and avian species combined, indicating a long-standing host-virus association. Structural and functional analyses of hemagglutinin and neuraminidase suggest that sialic acid is not a receptor for virus attachment or a substrate for release, indicating a unique mechanism of influenza A virus entry into host cells. These findings suggest that bats may be a significant and ancient reservoir for a diverse pool of influenza viruses. The study also found that several Peruvian bat species were infected by the virus, and serologic testing indicated a high prevalence of antibodies to the surface proteins. The results highlight the functional plasticity of influenza A viruses and the need for further research to understand the potential public health significance of these viruses. The study also identified that the bat influenza viruses form a monophyletic group, suggesting sustained transmission within this species. The research underscores the importance of bats as a potential source of influenza virus genetic diversity and the need for continued surveillance and study of these viruses.New World bats harbor diverse influenza A viruses. Researchers identified a novel influenza A virus, H18N11, in flat-faced fruit bats from Peru. Phylogenetic analysis showed that New World bats possess more influenza virus genetic diversity than all other mammalian and avian species combined, indicating a long-standing host-virus association. Structural and functional analyses of hemagglutinin and neuraminidase suggest that sialic acid is not a receptor for virus attachment or a substrate for release, indicating a unique mechanism of influenza A virus entry into host cells. These findings suggest that bats may be a significant and ancient reservoir for a diverse pool of influenza viruses. The study also found that several Peruvian bat species were infected by the virus, and serologic testing indicated a high prevalence of antibodies to the surface proteins. The results highlight the functional plasticity of influenza A viruses and the need for further research to understand the potential public health significance of these viruses. The study also identified that the bat influenza viruses form a monophyletic group, suggesting sustained transmission within this species. The research underscores the importance of bats as a potential source of influenza virus genetic diversity and the need for continued surveillance and study of these viruses.