Researchers in Italy recently examined the antiviral activity of tea tree oil. They found that it effectively inhibited H1N1 replication at doses that were not toxic to normal cells. Therefore, you may want to consider diffusing tea tree oil in your office space to help prevent H1N1 infection, and if you have already contracted it, you may want to diffuse it at home to protect other family members.
 
Lett Appl Microbiol. 2009 Sep 18. [Epub ahead of print]