A woman who recently returned from a trip to Mexico was being tested for swine flu at West Middlesex Hospital this afternoon after complaining of symptoms.

The woman checked herself into the accident and emergency department in Isleworth in the early hours of this morning, where medics then placed her into isolation.

A hospital spokesman said the patient had “flu-like symptoms,” and she would stay in over night with test results expected tomorrow afternoon.

He said: “As a precaution we admitted her to hospital, she has been isolated and tested at the moment and we are still awaiting the results.

“She is in isolation as a routine procedure. With any potential infectious disease like this we normally isolate someone until we find out more about them.”

The deadly virus is believed to have killed 152 people in Mexico, but no deaths have yet been reported outside the country.

A case was confirmed in Scotland yesterday as the UN warned of a potential pandemic.

A spokesman said this afternoon the woman was "stable, well and sitting up". She said: "We need to wait with everybody else and see how this pans out over time. At the moment we are not seeing any other cases."

NHS Hounslow’s director of public health, Dr Mike Robinson, said: “NHS Hounslow is continually working closely with other key agencies in Hounslow to prepare for a future pandemic influenza by developing a contingency plan.

"These well developed plans will at the appropriate time be put into action to reduce the impact, and help control the flu.

“The single most effective way to stop or slow the spread of diseases like pandemic flu is to prevent the spread of germs.

"Ensure you wash your hands regularly with soap and water and cover your mouth if you cough or sneeze.

"Clean hard surfaces, for example, door handles frequently using a normal cleaning product.

"It is important that children also follow this advice.”

Dr Robinson advised anyone concerned about swine flu to go to nhs.uk for updates and advice.

He added that anyone affected should monitor their health for seven days.

If they develop a feverish illness accompanied by one or more of a cough, sore throat, headache or muscle aches, they should stay at home and phone their GP or seek advice from NHS Direct by calling 0845 4647.

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