Health chiefs drew up a contingency plan for a flu pandemic in 1997, which included a widespread vaccination programme, the possible closure of schools and restricting international travel.

The plans have been revealed in archived papers which state that medics believed a pandemic was “imminent” and was likely to emerge in the Far East.

The files show that the Northern Ireland Department of Health, Social Services and Public Safety received a UK-wide Contingency Plan for Pandemic Influenza in March 1997.

The plan states: “The following conditions co-existing suggest that a pandemic is imminent – the emergence of a new strain of influenza virus which has a marked antigenic shift – a new virus; a high proportion of susceptible people in the population, ie with no immunity to the new virus either from vaccination or from previous infection with a similar virus; evidence that the new virus can spread and cause human disease.”

The document continues: “Typically, new shifted strains of influenza virus have emerged in the Far East and spread via Asia or the Antipodes towards Europe.

“If this occurs, some warning is likely before a new strain appears in the United Kingdom, although spread may be very rapid.”

The report states that any flu which originated in China would likely have a faster spread than the previous pandemic in 1968 due to “the opening of China to trade and tourism” and “increasing international movement of people and greater use of rapid methods of transportation”.

In response, then senior medical officer for Northern Ireland, Dr Elizabeth Mitchell, drafted a contingency plan for the region in December 1997 to assist the local health service in preparing draft arrangements.

The plan states: “Immunisation with appropriately formulated influenza vaccine can reduce the impact of influenza, particularly among those population groups most at risk of serious illness or death.

“An early priority of contingency arrangements will therefore be necessary to secure supplies of vaccine against the new strain and to immunise as many people as possible.”

National Archives records released
Dr Henrietta Campbell expressed concerns about avian influenza in 1997 (Paul Faith/PA)

The draft report continues: “In general, it is unlikely that the spread of influenza can be halted, but some slowing could possibly be achieved by reducing unnecessary, especially long distance travel, and by encouraging people suffering from the disease to stay at home.

“Closing schools is likely to cause some problems, especially for working parents, but would be an option to be considered, particularly if teacher absenteeism reached levels at which schools could not function.”

Dr Mitchell’s report also states that non-urgent hospital admissions, including serious but non-critical operations, will “need to be reviewed and may need to be suspended to make beds available.”

A letter from chief medical officer Dr Henrietta Campbell on December 17 1997 to all directors of public health and doctors in Northern Ireland expressed concern over an outbreak of Avian influenza in Hong Kong which had infected six people.