What a difference a week makes in China.
Effective May 4, 2009, a new regulation went into effect that temporarily suspends expedited processing (rush and express service) of all U.S. citizen visas to China.
It is unclear how this temporary suspension of expedited visa processing addresses China's concern about the swine flu outbreak in the United States. It is possible that applications from specific regions with high incidence rates will be more closely scrutinized. At any rate, this new regulation does not affect normal six business day processing.
Although I don't know for certain, I have to believe that a physical exam clearing the applicant of all contagious diseases would have to settle the matter if there were any concerns.
If you have plans to arrive in China within the next few months and don't already have your Z-visa, you will probably want to allow for more time than originally planned.
Stay tuned for latest updates.