1. Centers for Disease Control and Prevention, Fort Collins, Colorado, USA;
2. Saint-Antoine University Hospital, Paris, France;
3. University of Picardy, Amiens, France;
4. University Hospital of Lausanne, Lausanne, Switzerland;
5. National Institutes of Health, Bethesda, Maryland, USA;
6. University of Alabama at Birmingham, Birmingham, Alabama, USA;
7. Hvidovre Hospital, Hvidovre, Denmark