Letter: surveillance of Helicobacter pylori antibiotic resistance – authors' reply

*Primary Care Unit, Health Protection Agency, Gloucestershire Royal Hospital, Gloucester, UK. Endoscopy Unit, Gloucestershire Hospitals NHS Foundation Trust, Gloucester, UK. Statistics Unit, Health Protection Agency, London, UK. Public Health Wales Microbiology Bangor, Ysbyty Gwynedd, Bangor, UK. Helicobacter Reference Unit, Laboratory of Gastrointestinal Pathogens, HPA, Colindale, London, UK. **Institute of Medical Microbiology and Hygiene, University Hospital Freiburg, Freiburg, Germany. E-mail: cliodna.mcnulty@hpa.org.uk