[1] Univ Hosp, Dept Mol & Clin Med, Div Clin Microbiol, S-58185 Linkoping, Sweden
[2] Linkoping Univ, Dept Mol & Clin Med, S-58185 Linkoping, Sweden
[3] Lund Univ, Dept Med Microbiol, S-22100 Lund, Sweden
[4] Lund Univ, Dept Food Technol, S-22100 Lund, Sweden
[5] Gothenburg Univ, Dept Clin Bacteriol, S-41124 Gothenburg, Sweden