superspreader

noun3

1. •
   A person infected with a pathogen who is responsible for spreading it to many other people.
2. •
   [before a noun] An event or place which leads to the spread of an infectious disease to many people.
3. •
   A person or thing responsible for the widespread distribution of something regarded as dangerous or undesirable (for example, misinformation).

   • But whether they intend it or not, celebrities, politicians and others with large online followings can be superspreaders – not of the coronavirus but of dangerous or false information. — 2020