Above is a chart of worldwide cases of the COVID-19 coronavirus disease (data from here, skipping the first few days). The apparent spike in cases on February 12 is due to a change in how cases are diagnosed and reported.
There does not seem to be the exponential growth in cases that one would expect (see the badly-fitting blue curve), except at first. In fact, allowing for the “false spike,” growth seems to be almost linear (see the dashed purple line). This would probably be due to under-counting (the Chinese medical system can only diagnose a certain number of cases each day), although it offers some hope that quarantine measures may be working. Let us pray that they continue to work.