The World Health Organization warned Thursday that the Coronavirus outbreak in China represents a "high global risk" — but stopped short of declaring a global Public Health Emergency. The number of confirmed cases rose to over 500, with at least 18 deaths in China — and some experts warn the true number of cases could be much higher. As Henry Ridgwell reports, the coronavirus originated in the Chinese city of Wuhan, where authorities are taking strict measures to try to halt the spread of the disease.