Just one more consperacy theory too chew on. British soldiers sickened by mystery fever in Afghanistan London-AP -- Authorities are trying to trace the cause of a mysterious fever in Afghanistan. British officials say 18 staff members at a British military field hospital near Kabul have fallen ill with the unidentified fever. They say two of the soldiers are "very seriously ill" and have been evacuated to hospitals in Europe. The fever appears to be contagious. Copyright 2002 Associated Press. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.