From 28 March 2020, access to China is limited to people holding a diplomatic visa or a courtesy C visa.
People coming to China for “necessary economic, trade, scientific or technological activities or out of emergency humanitarian needs” may get access as well. The Chinese embassy in your country of residence will decide this.
However, if you can get a visa after 28 March, then you will have access to China. In this case, you will face a 14 day quarantine period at arrival.
The following text is the official announcement on the website of the Ministry of Foreign Affairs.
In view of the rapid spread of COVID-19 across the world, China has decided to temporarily suspend the entry into China by foreign nationals holding visas or residence permits still valid to the time of this announcement, effective from 0 a.m., 28 march 2020. Entry by foreign nationals with APEC Business Travel Cards will be suspended as well. Policies including port visas, 24/72/144-hour visa-free transit policy, Hainan 30-day visa-free policy, 15-day visa-free policy specified for foreign cruise-group-tour through Shanghai Port, Guangdong 144-hour visa-free policy specified for foreign tour groups from Hong Kong or Macao SAR, and Guangxi 15-day visa-free policy specified for foreign tour groups of ASEAN countries will also be temporarily suspended. Entry with diplomatic, service, courtesy or C visas will not be affected. Foreign nationals coming to China for necessary economic, trade, scientific or technological activities or out of emergency humanitarian needs may apply for visas at Chinese embassies or consulates. Entry by foreign nationals with visas issued after this announcement will not be affected.Ministry of Foreign Affairs of the People’s Republic of China
The suspension is a temporary measure that China is compelled to take in light of the outbreak situation and the practices of other countries. China will stay in close touch with all sides and properly handle personnel exchanges with the rest of the world under the special circumstances. The above-mentioned measures will be calibrated in light of the evolving situation and announced accordingly.