Dr James Rudge, of the London School of Hygiene and Tropical Medicine, said that limited transmission between humans is not surprising and has been seen before in other bird flu viruses, such as H5N1.
“Our findings reinforce that the novel virus possesses the potential for pandemic spread,”
He added: “It would be a worry if we start to see longer chains of transmission between people, when one person infects someone else, who in turn infects more people, and so on.
And particularly if each infected case goes on to infect, on average, more than one other person, this would be a strong warning sign that we might be in the early stages of an epidemic.” (source)