Screwworm myiasis, a disease in which blowflies lay their eggs around wounds or mucous membranes of mammalian (including human) hosts and the developing maggots eat the flesh of their living host, has recently emerged in Yemen.  First reports in Yemen come from December 2007.  The screwworm larvae are very sensitive to cold temperatures so one wonders if this emergence may be related to global warming.  The disease used to be endemic in the  southern United States but was eliminated some time ago. If the emergence of this infection on the Arabian Peninsula is indeed related to changing (probably nighttime) temperatures, then one also has to wonder about the possibility for re-emergence in North America...