Information Letter

14 September 2006

Information Letter 10/2006

To:   Board Level and Day to Day Contacts of Water and Sewerage Companies and Water Companies in England and Wales.

Dear Sir/Madam

Cryptosporidiosis in England and Wales

1. The purpose of this letter is to update the industry on the matters covered in DWI Information Letter 17/2005 issued in December 2005.
   

Background

2. In the autumn of 2005 an increase in the expected number of cases of human cryptosporidiosis was reported by the Health Protection Agency. Most of these infections were caused by Cryptosporidium hominis, the human strain. Three outbreaks were under investigation by outbreak control teams and two of these (one in South England, one in North Wales) were linked putatively to the public water supply. The third was linked to a swimming pool. Information Letter 17/2005 gave notice under Regulation 27 (5) that water companies were to review their cryptosporidium risk assessments for surface water derived supplies by 30th April 2006. It also provided guidance on risk assessment criteria, monitoring and communications. The Inspectorate undertook to review the relevant regulations and guidance in light of any lessons learnt from companies’ revised risk assessments and the reports of outbreak control teams.


Guidance

3. The Third Report of the Group of Experts on Cryptosporidium in Water Supplies, known as the Bouchier Report, was published in November 1998. The Cryptosporidium Regulations and associated Guidance were implemented in 1999. As part of the Inspectorate’s commitment in IL 17/2005 , the Health Protection Agency (HPA) was commissioned in spring 2006 to produce a report updating knowledge on Cryptosporidiosis (epidemiology and health surveillance data) since the publication of the Bouchier Report. I am pleased to inform you that this report, funded by Defra under contract DWI 70/2/201, entitled Cryptosporidiosis: A Report on the Surveillance and Epidemiology of Cryptosporidium infections in England and Wales is now available on the Inspectorate’s website. Attached for your information as Annex A and B to this letter are two extracts from the report (a) Summary; (b)
   Conclusions and Recommendations.
   
   
4. In its report the HPA has concluded that there is good evidence from health surveillance data to show that there has been an overall reduction in cryptosporidiosis in the past five years associated with the introduction of the Cryptosporidium regulations and consequential improvements in water treatment. These benefits are especially evident in the first half of the year. However the HPA also notes that there may be some water related risk requiring further research in relation to infections occurring in the latter half of the year. As we have now entered this period of heightened risk, companies are reminded that they should have carried out work to be satisfied that all relevant operational and stakeholder communication arrangements for cryptosporidium risk management are fit for purpose generally, and specifically in respect of those matters covered by IL 17/2005 . Inspectors will be monitoring the position closely and companies are requested to provide their company inspector with regular status briefings over the coming months.
   
   
5. Companies are reminded that all the recommendations addressed to the water industry in the Bouchier Report, together with those in the First and Second Reports of the Expert Group (known as the Badenoch Reports), including associated guidance documents on, for example, water treatment, remain valid and sufficient time has elapsed for these to now reflect good practice. Attention is also drawn to other important best practice documents which contain guidance on cryptosporidium risk management, for example, The Microbiology of Drinking Water 2002.


Regulation 27 Risk Assessments

6. The Inspectorate is able to confirm that most companies submitted updated risk assessments for surface water derived water supplies by 30 April 2006 and all had done so by 31 May. In one fifth (35) of the total of 168 risk assessments, the company had changed its conclusion regarding risk from the previous assessment. In 4 cases, the conclusion had changed from Not at Risk to Significant Risk and for the remaining 31 cases the conclusion had changed from Significant Risk to Not at Risk. The Inspectorate has noted that for some works the review in 2006 was the first to have taken place since 1999.
   
   
7. Companies are reminded that in order to demonstrate compliance with Regulation 27 (4) a company would be expected to have in place documentation showing that regular risk assessment reviews had taken place since 1999. Regulation 27 (4) applies to groundwater as well as surface water works, and to all works, not just those assessed originally as being at Significant Risk.
   
   
8. In June 2006 the Inspectorate commissioned the University of East Anglia (UEA) to update the cryptosporidium risk assessment database created during a previous research project (the CMAW study available at ) to include the 2006 risk assessment data. UEA have recently completed this exercise and this tool will be used by the Inspectorate to evaluate the operation of the cryptosporidium risk assessment process.
   

Outbreak Control Team Reports

9. The Bouchier Report contains a recommendation (1.2.59) that the reports of Outbreak Control Teams (OCT) on waterborne outbreaks should be formally received and recommendations commented upon by the Inspectorate so that any lessons learnt are communicated widely. The Inspectorate has been kept fully updated as to progress with the production of these OCT reports. The Inspectorate’s own separate investigations are substantively complete.
   

Next Steps

10. The Inspectorate’s regulations team will be in direct contact in the near future with each company who submitted a revised assessment of risk at one or more of their works. Enquiries on this matter should be directed to Joanna.gigg@defra.gsi.gov.uk
    
    
11. The Inspectorate is considering the conclusions and recommendations in the HPA report and is consulting on how these are most appropriately taken forward. Not all of the matters raised are of direct concern to the water industry; however, if there are matters you wish to draw to my attention regarding the content of the HPA report then please address these to peter.marsden@defra.gsi.gov.uk .
    
    
12. I will write to you again when I am in a position to advise you about any industry wide lessons to be learnt as a consequence of the investigations into the outbreaks in autumn 2005 by the Inspectorate and others, including those water companies directly involved. Information already available to the Inspectorate is being taken into consideration in the development of the Defra consultation document regarding proposals to amend the Water Supply (Water Quality) regulations in 2007.
    
    
13. I am copying this letter to Pamela Taylor, Chief Executive, Water UK; Richard Wood, Water Supply and Regulation Division, Department for Environment, Food and Rural Affairs; June Milligan, Environment Division, Welsh Assembly Government; Colin McLaren, Drinking Water Quality Regulator for Scotland; Randal Scott, Drinking Water Inspectorate for Northern Ireland; Chairs of the Consumer Council for Water Committees; Rowena Tye, Office of Water Services; Tony Smith, Chief Executive, Consumer Council for Water; Tony Warn, Environment Agency; Nigel Harrison, Food Standards Agency; Gary Coleman and Gordon Nichols of the Health Protection Agency and Hilary Aldridge, Environment Agency.
    
    
14. This letter is being sent electronically to Board Level and day to day contacts. Please acknowledge receipt by email to dwi.informationletters@defra.gsi.gov.uk . Hard copies are not being sent but the letter may be freely copied.

 

Yours faithfully



Prof. Jeni Colbourne MBE
Chief Inspector of Drinking Water

 

Annex A (MS Word format)
Annex B (MS Word format)