Five Smallpox Management and Reaction Teams (SMART) are on standby in the region in the event of a release of the disease into the population.

Although this is considered highly unlikely, the teams undergo specialist training and are inoculated against smallpox.

Smallpox was certified as being eradicated in 1980 after a global vaccination campaign co-ordinated by the World Health Organisation.

Remaining laboratory stocks were either destroyed or transferred to two highly secure facilities in the US and Russia.

However, uncertainty over whether all stocks have been accounted for and the threat of terrorism has prompted the Department of Health to prepare contingency plans.

Containment measures

Each SMART has up to five members, who have regular jobs within the NHS and Health Protection Agency,

They include a public health specialist (team leader), a consultant in infectious diseases, a communicable disease control nurse and a regular clinical nurse.

They are co-ordinated by one of nine Regional Smallpox Diagnosis and Response Groups based across England.

There are 45 SMART on stand-by across England.

Their job would be to investigate any suspected cases at short notice and put in place initial containment measures.

The spread of the virus would be contained by implementing a strategy known as "ring vaccination" - inoculating everyone who may have had contact with, or had been around, the patient.

"I don't think a smallpox incident will happen but I'm reassured that we have a way of dealing with it"
Dr Joe Kearney

The East of England Smallpox Plan, obtained under the Freedom Of Information laws, states that the majority of the population is susceptible due to the suspension of routine vaccination and increased mobility.

The East's plan also provides for the vaccination of the entire regional population within five days in the event of a major outbreak .

In the event of large numbers of people being systematically infected by a determined terrorist, Dr Joe Kearney, Regional Director of the Health Protection Agency for the East of England, said there was sufficient vaccine in the UK for the entire population.

Smallpox has a high mortality rate - up to 50% according to Dr Kearney - and is highly infectious.

Pete Zimmerman, Professor of Science and Security at Kings College London, said: "Smallpox is probably the greatest killer of human beings that has ever been known as a single disease."

Its removal from nature in the 1970s is regarded as one of history's greatest medical achievements.

The last case in the world was in 1978 when a medical photographer called Janet Parker died after being accidentally infected at Birmingham Medical School.

It was this incident which prompted the WHO to confine all known experimental stocks to the two secure labs at Atlanta, USA and Novosibirisk in Russia.

The last case of endemic smallpox in Britain was recorded in the 1930's and in the East, one of the last outbreaks occurred in 1928.

A search of the county Medical Officer's records for Norfolk shows that 42 cases were recorded for that year.

One account records how an infected man came off a ship at Great Yarmouth and walked to Norwich, coming into contact with many people.

Posters were put up across the city and warnings were flashed on cinema screens urging people to report themselves if they felt ill. The last case in Norfolk was in 1935.

The chances of another outbreak in the UK are incredibly slim.

Dr Kearney said: "Personally, I don't think a smallpox incident will happen but I'm reassured that we have a way of dealing with it and I'm confident that the SMART teams we have in place would be the appropriate way to deal with it."