From bad to worse
How the avian flu must change before it can trigger a human pandemic
For that nightmare to unfold, however, the virus, a subtype known as H5N1, would have to undergo a major transformation, changing from a pathogen efficient at infecting cells in the guts of birds and spreading through feces-contaminated water into one adept at infecting human lung tissue and spreading through the air. So far, that has not happened.
https://www.science.org/content/article/bad-worse-avian-flu-must-change-trigger-human-pandemic #AvianFlu #mutate #pandemic