A bunch of others are wondering that also. The Chinese government has been under strong critisism for trying to hide SARS patients, even to the ridiculous length of driving dozens around in ambulances while WHO officials were inspecting the hospitals. That attempted coverup is very suspicious as regarding a possible Chinese bio-leak, but on the other hand, communist regimes are infamous for trying to cover up disasters, and a naturally arising epidemic might be another example of trying to make everything look nice.
I forgot - we live in a disease-free world ...