Researchers have witnessed two viruses – influenza A and respiratory syncytial virus – fuse together to form a single, hybrid virus.
While competition between viruses has been researched in some detail, this new finding provides researchers with an unusual example of one virus coopting another for its own benefits.
The hybrid virus looks like a gecko's foot under the microscope, with respiratory syncytial virus forming the legs and influenza A virus forming the toes. Human lung cells were exposed to both viruses, as well as each virus individually as a control group. An assortment of microscopy techniques then revealed filamentous structures consistent with a hybrid of both virus particles.
The hybrid also spread into cells that lacked influenza receptors, which could allow influenza A to move further down the respiratory tract into the lungs and lead to more severe infections.