Senir public health doctors have issued a "don't panic" warning after it was revealed that suspected cases of the Sars virus are being investigated in the region.

Dr Vivien Hollyoak, a specialist from Health Protection Agency North-East, said no probable cases of the Far East virus had been confirmed in the region.

"We can rest assured that we are in the fortunate position of having this under control in this country," said Dr Hollyoak.

While at least 17 people are known to have been admitted to hospitals in the region with suspected Sars - Severe Acute Respiratory Syndrome - Dr Hollyoak stressed that the tests were being carried out as a precautionary measure.

Today a spokeswoman for South Tees Hospitals NHS Trust confirmed that one suspected case has been tested at the Friarage Hospital in Northallerton and given the all clear.

Doctors at the South Tees trust are currently awaiting results on one other suspected case. At North Tees and Hartlepool NHS Trust, doctors had carried out tests on one suspected case, which proved negative.

Earlier in the week, doctors at Newcastle General Hospital said they had tested at least a dozen suspected cases.

Two women patients who have returned from Hong Kong complaining of flu-like symptoms, a 52 year old and a woman in her 40s are currently being kept in isolation at the Newcastle hospital.

But infectious diseases specialist Dr Ed Ong stressed that it was "highly unlikely" the women had the virus.

The Sars virus, which is believed to be linked to the common cold, has been spread globally through air travel, with most cases in Asia.

More than 130 people have died from the virus worldwide and about 3,000 people have been infected. So far six probable British Sars cases have been identified.

Four of the other UK's probable cases have recovered. A fifth person is in a stable condition at North Manchester General Hospital and a sixth is in London's Northwick Hospital.

Dr Hollyoak said all doctors had been alerted to look out for patients who had recently returned from Hong Hong or southern China and developed sudden fever and flu-like symptoms

"We only need to be concerned if they become unwell within 10 days of having returned. If they were there six weeks ago they don't need to worry," said Dr Hollyoak.