Corona virus is especially dangerous to Asians. China lab got a sample and was studying it. It got out, or a foreign government or faction of a foreign government released it to make it look like it was China's fault.
There's no advantage for Chian to release it on purpose. Even if the virus is not super lethal (>5%), the economic impact of the release will set China back several years. If it is specifically targeted to Asians, or has just evolved to be more lethal to Asians, it is unlikely that China did the engineering.