1. TNO Prins Maurits Laboratory, Rijswijk, The Netherlands
2. Swedish Defence Research Agency
3. Department of Clinical Microbiology, Bacteriology
4. Department of Clinical Microbiology, Infectious Diseases, Umeå University, Umeå, Sweden
5. Defence Science and Technology Laboratory, CBS Porton Down, Salisbury
6. Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom