BBC adds that 300 people at the Hong Kong hotel the man was staying at are being quarantined and police wearing masks are guarding the hotel.
Twitterers in Hong Kong provided context about the impact of the case:
Actress4life_hk (Hong Kong) The frist swine flu case just happened in Hong Kong..!!This is also the frist day of Golden week holiday a long weekend in HK!...Bad!!! HotJaney (Hong Kong) There's just been a confirmed case of Swine flu in Wan Chai in Hong Kong 2 hours ago. Everybody is wearing masks. ruisi1 (Hong Kong) Swine flu has hit the shores of Hong Kong! People here are ready to party like it's 2003. Bust out the masks and pass the sanitizer!
One Twitterer used the incident to voice frustration with mainland China.
victorsteve (Hong Kong) the mainland chinese continue to bestow gifts on hong kong... they sent the first swine flu case across the border just yesterday...
Here's some other initial reaction from Hong Kong Twitter users:
AndreMartin (Hong Kong) Either the Hong Kong hotel with a swine flu infected guest has also been sealed off communications or there is just no Twitter user inside.. kaylawebley (Hong Kong) 1st case of swine flu reported in Asia is in Hong Kong, in my neighborhood nonetheless. 300 people quarantined. Time to break out the mask? caitlinx852 (Hong Kong) can't believe this swine flu [expletive] is in hong kong :(
what a bad summer this is going to be!