[1] UNIV HAMBURG,KRANKENHAUS EPPENDORF,D-522000 HAMBURG 20,FED REP GER
[2] CTR DIS CONTROL,DIV BACTERIAL DIS,ATLANTA,GA 30333
[3] UNIV MELBOURNE,DEPT MICROBIOL,PARKVILLE,VIC 3052,AUSTRALIA
[4] UNIFORMED SERV UNIV HLTH SCI,DEPT MICROBIOL,BETHESDA,MD 20814
[5] CANADIAN CTR DIS CONTROL,OTTAWA K1A 0L2,ONTARIO,CANADA
[6] UNIV MARYLAND,CTR VACCINE DEV,BALTIMORE,MD 21201