"A man in San Diego was infected with the vaccinia virus — the virus in the smallpox vaccine — in June, 2012 after having sexual contact with someone who'd recently been vaccinated, according to a new report from the Centers for Disease Control and Prevention."
Some spills (infections) leave stains others are washed away totally with water or some other solvent.
FAIR USE NOTICE:
This site may at times contain copyrighted material the use of which has not always been specifically authorized by the copyright owner. We are making such material available in our efforts to advance understanding of environmental, political, human rights, economic, democracy, scientific, and social justice issues, etc. We believe this constitutes a 'fair use' of any such copyrighted material as provided for in section 107 of the US Copyright Law. If you wish to use copyrighted material from this site for purposes of your own that go beyond 'fair use', you must obtain permission from the copyright owner.
For more information go to: http://www.law.cornell.edu/uscode/17/107.shtml