Alarm over the coronavirus that emerged in Wuhan, China, in December is driven by its rapid spread and the fact that infectious disease experts cannot yet know how deadly or contagious it is.
It has killed more than 900 people, most of them in China, and has spread to at least 27 countries and territories. The two deaths outside mainland China were in Hong Kong and the Philippines.
The new cases in England were all known contacts of a previously confirmed British patient in France, and were identified by public health officials working to trace possible cases.