Of course. But Hong Kong is administered separately, and has its own "Chief Executive". Hong Kong is much more western, and its press is much more free, than elsewhere in China.
The reported numbers for SARS in Hong Kong and China are consistently reported separately. The numbers from China are transparently bogus. I have not seen anything casting doubt on the Hong Kong numbers.
Hong Kong has been much more open, and much more cooperative, than the rest of China throughout this whole ordeal. To lump them together may be technically correct, but would actually be quite misleading.
That said, I am sure the government of China could tell Hong Kong to jump, and the government of Hong Kong would say "How high?" Would Beijing tell Hong Kong to put the lid on?
Even China can not successfuly minimize the problem forever. There is simply too much contact between China and the rest of the world to keep a story of this magnitude under wraps. They are still trying to manage the story as a public relations matter, but the damage only gets worse as their credibility continues to plummet.