Surveillance of the bioterrorist threat: a primary care response

Threats from bioterrorism are of national and international concern. We outline a system of disease surveillance covering a selection of diseases linked to potential bioterrorist threats, based on the weekly returns service of the Royal College of General Practitioners and covering a surveillance population of 650,000 in England and Wales. Practices record working diagnoses and the episode type (distinguishing new episodes of illness from ongoing consultations) on patients' computerised medical records. These are interrogated twice weekly by using automated routines. The registered population and persons consulting for each Read code (group of codes) are counted in sex and age specific groups and the data forwarded electronically to the Research Unit, where the results are consolidated by region (North, Central, South). Weekly incidence rates between October 2001 and September 2002 were compared with the weekly average over the past seven years for 13 selected conditions. Detailed data are presented for three conditions (asthma, infections of the skin, disorders of the peripheral nervous system). For asthma increased incidence was reported in weeks 31 and 32 of 2002, predominantly in the Central region. For the other two conditions no unusual peaks of incidence were observed in any region. Operational research based on disciplined recording of morbidity in general practice can deliver timely surveillance data on bioterrorist threats.