Epidemiology and Infection

Review Article

Outbreaks of waterborne infectious intestinal disease in England and Wales, 1992–2003

A. SMITH a1c1, M. REACHER a1, W. SMERDON a1, G. K. ADAK a1, G. NICHOLS a1 and R. M. CHALMERS a2
a1 Health Protection Agency, Centre for Infections London, UK
a2 Cryptosporidium Reference Unit, NPHS Microbiology Swansea, Singleton Hospital, Sketty, Swansea, UK

Article author query
smith a   [PubMed][Google Scholar] 
reacher m   [PubMed][Google Scholar] 
smerdon w   [PubMed][Google Scholar] 
adak gk   [PubMed][Google Scholar] 
nichols g   [PubMed][Google Scholar] 
chalmers rm   [PubMed][Google Scholar] 


We reviewed the epidemiological and microbiological characteristics of 89 reported outbreaks of waterborne infectious intestinal disease affecting 4321 people in England and Wales over the period 1992–2003. Public water supplies were implicated in 24 outbreaks (27%), private water supplies in 25 (28%), swimming pools in 35 (39%) and other sources in five outbreaks (6%). Cryptosporidium was implicated in 69% of outbreaks, Campylobacter sp. in 14%, Giardia in 2%, E. coli O157 in 3% and Astrovirus in 1%. From 2000, there was a consistent decline in the number of outbreaks of waterborne disease associated with public water supplies. The incidence rate of outbreaks in recipients of private water supplies may be as high as 35 times the rate in those receiving public water supplies (1830 vs. 53 per million population). Private water suppliers need to be aware of the importance of adequate treatment and the prevention of faecal contamination of storage water. Swimming-pool operators need to ensure chlorination and in particular adequate filtration measures are in place.

(Accepted March 15 2006)
(Published Online May 11 2006)

c1 Health Protection Agency, Centre for Infections, 61 Colindale Avenue, London NW9 5EQ, UK. (Email: alan.smith@dh.gsi.gov.uk)