An urgent warning has been issued about the tap water in thousands of Surrey and Kent homes.

SES Water said routine tests have showed that its water supplies could be affected by the deadly E-coli bacteria.

The company is advising those living in Oxted, Redhill, Limpsfield, Godstone and Sevenoaks to boil their drinking water and then let it cool before drinking, preparing food or brushing teeth.

It said that pets should also be given boiled tap water, and that boiled water can be kept in the fridge, and should be covered and used within 24 hours.

SES issued a list of more than 400 affected postcodes along with full advice and guidance on boiling water.

It is encouraging customers to talk to their neighbours to share the advice with them.

A spokesperson said that SES is working to investigate the problem and restore supplies to "usual high standards".

They apologised to everyone affected and reassured that "everything possible is being done to do further testing".

Most vulnerable customers are being supported "as a priority" SES added.

What is E.coli?

NHS England said: "Escherichia Coli (E. coli) is a gram negative rod shaped bacteria found in the gut of most people and animals. E.coli does not usually cause any problems whilst it is living in the gut, but if the bacteria contaminates areas of vulnerability (wounds, catheter sites etc.), infection can occur."

What are the risks of E.coli?

• Urinary catheterisation

• Dehydration

• Older age

• Prostate problems (enlargement, TURP etc.)

• Gall bladder or kidney stones

• Long term conditions (COPD, bronchitis, diabetes)

• Open wounds or ulcers

• Recent hospital admission or surgical procedures

• IV line

Why does E.coli matter?

NHS England said: "Gram negative bacteria account for one third of all blood stream infections (BSIs) and of this third, 65% are E. coli. In the 2015/16 financial year E. coli was responsible for 5,500 NHS patient deaths and by 2018, E. coli BSI will cost the NHS around £2.3 billion. 668 cases of E.coli bacteraemia were identified in Leeds (2016/17). 68% were community onset."

How can E.coli bacteria be prevented?

As a healthcare professional, breaking the chain of infection is one of the most effective ways of preventing any bacteraemia.

This includes:

• Good hand hygiene technique

• Complying with the 5 moments of hand hygiene

• Appropriate PPE usage

• Reviewing the need for invasive devices such as urinary catheters

• Timely diagnosis of infections and appropriate prescribing

• Prescribing based on sensitivities

Patients should also be encouraged to conduct effective hand hygiene:

• After toileting

• Before preparing and eating food

• Before handling invasive devices such as IV lines and urinary catheter

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