All non-urgent elective surgery has been cancelled for tomorrow. This includes all pre-arranged admissions for Christchurch, Christchurch Women's and Burwood Hospitals. Scheduled Caesarean sections and inductions will continue. Affected patients are being contacted.

Outpatient clinics are still running, however, the advice to the public is come in if you can make your appointment - but if you can't get in to your clinic the DHB will be in touch to reschedule at a later date.

The flow of patients to hospital is steady and staff are coping well.

Akaroa Hospital has been closed and patients have been transferred to other facilities.

Lincoln Maternity Hospital and Burwood Birthing Unit will be closed until further notice.

Private hospitals have also deferred major surgery to help maintain capacity in the health system.

All main hospital buildings have been checked to ensure they are safe and structurally sound. Engineers will be continuing to work through all facilities identifying what repairs may be required.

Public Health messages

People need to take the following advice to avoid getting sick with stomach bugs and other illnesses.

1)People living in the Christchurch, Waimakariri and Selwyn districts should assume at the moment that tap water is unsafe and contaminated until advised by the Council that it is safe. All tap water should be boiled for one minute before drinking, brushing teeth or washing/preparing food. (Note: If you are boiling water in a pot - boil for one minute - if it's in a jug, bring it to the boil twice)

Councils will be testing water supplies intensively over the next few days and will advise when water is safe to use without boiling. Even though water may look clear, it should be treated as contaminated and unsafe to drink due to damaged underground water and sewage pipes.

2) Avoid contact with sewage. Assume river, sea water and any other surface water is contaminated with sewage. Stay away and do not swim, fish or gather shellfish in the sea, Canterbury rivers or any areas of standing water until notified.

3) Use as little water as possible to flush your toilet if you have water. If you don't have water, make a temporary toilet with a bin lined with two plastic bags. Cover the bin between uses. The contents can be buried when the bin is no longer needed. Details of how to make a temporary toilet can be found at http://www.moh.govt.nz/moh.nsf/indexmh/protecting-your-health-in-an-emergency

4) Remember hand washing stops diseases spreading. Cold water is fine as long as you use soap and dry your hands thoroughly. If you do not have water, alcohol gel is a good alternative. You don't need to dry your hands if you use alcohol gel.

5) It is important for people to look after each other. Keep in touch with families, friends and neighbours and support each other.

6) If you are unwell with a minor injury or illness and need medical assistance call your General Practice or nearest after hours surgery. Please keep the Emergency Department for emergencies only. If you need an ambulance dial 111.

7) Dishwashers should only be used on a full hot wash and dry cycle with detergent.

GASTROENTERITIS

There have been some reports of gastro enteritis at one of the Welfare facilities set up in Christchurch.

Two families at a Linwood welfare facility have gastro enteritis. It is not clear whether the infection is due to consuming contaminated water, or whether the infection pre dates Saturday morning's earthquake. It does not appear that infection was conveyed from one family to another.

Appropriate infection control measures are in place to manage this. The affected families have been isolated, and support is being given by St John and a nurse. Tests are underway to try and establish the causative organism.

Medical Officer of Health for Canterbury, Dr. Ramon Pink, said "Although the cause is not yet known for these two clusters, this is an important reminder that we should all be boiling our water thoroughly, especially any water which comes into contact with our mouth - drinking water, water for cleaning our teeth and water which is used for cleaning vegetables, salads or fruits".

The Communicable Disease Team of the Community & Public Health Division of Canterbury District Health board is monitoring this outbreak. At this time no other welfare centre has been affected and there is no evidence of spread to anyone outside these two families.