1. Statens Serum Institut, Copenhagen, Denmark.
2. Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark.
3. Hvidovre University Hospital, Hvidovre, Denmark.
4. Skejby Hospital, Aarhus, Denmark.
5. Odense University Hospital, Odense, Denmark.
6. Aalborg Hospital, Aalborg Denmark.
7. Kolding Hospital, Kolding, Denmark.
8. Hillerød Hospital, Hillerød, Denmark.