Foreign doctors and nurses are trying, for instance, to stem the spread of infectious diseases.

ECONOMIST: Western man��s burden

The formation of such paramilitary groups was stepped up across Indonesia late last year, ostensibly to stem the rapid spread of violence and rioting.

ECONOMIST: East Timor

In 1997, before he was charged, authorities in the western New York city of Jamestown took the unusual step of announcing publicly that Williams was HIV positive in an effort to stem further spread of the virus by Williams' partners to others.

WSJ: Lawyer: NY man at center of HIV scare not positive

South Korean forces have partnered with us to prevent piracy off the shores of Africa and stem the spread of weapons of mass destruction.

WHITEHOUSE: President Obama and President Lee Press Availability

We must stem the spread of foreclosures and falling home values for all Americans and do everything we can to help responsible homeowners stay in their homes, something I will talk more about tomorrow.

CNN: Obama's remarks on signing the stimulus plan