1 Department of Clinical Sciences, Lund University/CRC, Skåne University Hospital, Malmö, Sweden.
2 IHRC, Inc, under contract to Polio and Picornavirus Laboratory Branch, Centers for Disease Control and Prevention, Division of Viral Diseases, Atlanta GA, USA.
3 Polio and Picornavirus Laboratory Branch, Centers for Disease Control and Prevention, Atlanta, Georgia, USA.
4 Kristianstad University, Kristianstad, Sweden.
5 Department of Paediatrics, Östersund Hospital, Östersund, Sweden.