spread among

Although they have been around for nearly three decades in birds, the unprecedented spread among U.S. dairy cattle this year is alarming: The viruses have evolved to thrive within mammals.

The virus then spread among animals held in close quarters indoors, as well as to their human handlers.

In the United States, bird flu has also spread among dairy cows.

But its core ideas - in particular an opposition to illegal immigration, mixed with indiscriminate and racist claims about Muslims - are very much alive, and loudly and widely spread among sympathisers online.

Panic spread among Democrats who believed they were heading for a defeat that would give Trump control of the White House and both houses of Congress.